U.S. patent application number 17/286274 was filed with the patent office on 2021-11-18 for dielectric copolymer materials.
This patent application is currently assigned to Merck Patent GmbH. The applicant listed for this patent is Merck Patent GmbH. Invention is credited to Karsten KOPPE, Gregor LARBIG, Frank MEYER, Pawel MISKIEWICZ, Joerg PAHNKE.
Application Number | 20210355381 17/286274 |
Document ID | / |
Family ID | 1000005806764 |
Filed Date | 2021-11-18 |
United States Patent
Application |
20210355381 |
Kind Code |
A1 |
LARBIG; Gregor ; et
al. |
November 18, 2021 |
DIELECTRIC COPOLYMER MATERIALS
Abstract
The present invention relates to a polymerizable mixture which
can be used to form a dielectric material for the preparation of
passivation layers in electronic devices. The polymerizable mixture
comprises a first monomer and a second monomer which may react to
form a copolymer providing excellent film forming capability,
excellent thermal properties and excellent mechanical properties.
There is further provided a method for forming said copolymers and
an electronic device containing said copolymers as dielectric
material. Beyond that, the present invention relates to a
manufacturing method for preparing a packaged microelectronic
structure and to a microelectronic device comprising said packaged
microelectronic structure formed by said manufacturing method.
Inventors: |
LARBIG; Gregor; (Gelnhausen,
DE) ; MISKIEWICZ; Pawel; (Neu-Isenburg, DE) ;
MEYER; Frank; (Glashuetten, DE) ; PAHNKE; Joerg;
(Darmstadt, DE) ; KOPPE; Karsten; (Darmstadt,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Merck Patent GmbH |
Darmstadt |
|
DE |
|
|
Assignee: |
Merck Patent GmbH
Darmstadt
DE
|
Family ID: |
1000005806764 |
Appl. No.: |
17/286274 |
Filed: |
October 15, 2019 |
PCT Filed: |
October 15, 2019 |
PCT NO: |
PCT/EP2019/077837 |
371 Date: |
April 16, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C09K 2219/03 20130101;
C09K 2019/0448 20130101; C09K 19/02 20130101; C09K 2019/2078
20130101; C09K 19/2028 20130101; C09K 19/3483 20130101; C08G 73/10
20130101; C08G 2250/00 20130101; C08G 77/045 20130101; B82Y 20/00
20130101 |
International
Class: |
C09K 19/20 20060101
C09K019/20; C09K 19/02 20060101 C09K019/02; C09K 19/34 20060101
C09K019/34; C08G 77/04 20060101 C08G077/04; C08G 73/10 20060101
C08G073/10 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 18, 2018 |
EP |
18201357.3 |
Nov 12, 2018 |
EP |
18205766.1 |
Claims
1. A polymerizable mixture comprising a first monomer and a second
monomer, wherein the first monomer is one or more compound
represented by Formula (1), and wherein the second monomer is one
or more bi- or multifunctional compound capable of reacting with
the first monomer to give a copolymer:
P.sup.1-Sp.sup.1-(MG-Sp.sup.1).sub.m--P.sup.1 Formula (1) wherein:
m is an integer from 1 to 60; P.sup.1 denotes ##STR00056## wherein
V.sup.1 is H, and V.sup.2 is alkyl with 1 to 6 carbon atoms, F, Cl
or CN; or V.sup.1 and V.sup.2 are independently of one another
alkyl with 1 to 6 carbon atoms, F, Cl or CN; Sp.sup.1 denotes at
each occurrence a spacer group (Sp) or a single bond; MG is a
rod-shaped mesogenic group, which is preferably selected from
Formula (2):
-(A.sup.21-Z.sup.21).sub.k-A.sup.22-(Z.sup.22-A.sup.23).sub.l-
Formula (2) wherein: A.sup.21 to A.sup.23 are independently and at
each occurrence independently of one another an aryl group,
heteroaryl group, heterocyclic group, alicyclic group or cyclic
imide group optionally being substituted by one or more identical
or different groups L; Z.sup.21 and Z.sup.22 are independently and
at each occurrence independently from each other, --O--, --S--,
--CO--, --COO--, --OCO--, --S--CO--, --CO--S--, --O-- COO--,
--CO--NR.sup.01--, --NR.sup.01--CO--, --NR.sup.01--CO--NR.sup.02,
--NR.sup.01--CO--O--, --O--CO--NR.sup.01--, --OCH.sub.2--,
--CH.sub.2O--, --SCH.sub.2--, --CH.sub.2S--, --CF.sub.2O--,
--OCF.sub.2--, --CF.sub.2S--, --SCF.sub.2--, --CH.sub.2CH.sub.2--,
--(CH.sub.2).sub.4--, --CF.sub.2CH.sub.2--, --CH.sub.2CF.sub.2--,
--CF.sub.2CF.sub.2--, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--,
--CH.dbd.CR.sup.01--, --CY.sup.01=CY.sup.02--, --C.dbd.C--,
--CH.dbd.CH--COO--, --OCO--CH.dbd.CH--, or a single bond; R.sup.01
and R.sup.02 each, independently of one another, denote H or alkyl
having 1 to 12 C atoms; L is F, Cl, Br, I, --CN, --NO.sub.2, --NCO,
--NCS, --OCN, --SCN, --C(.dbd.O)NR.sup.xxR.sup.yy,
--C(.dbd.O)OR.sup.xx, --C(.dbd.O)R.sup.xx, --NR.sup.xxR.sup.yy,
--OH, --SF.sub.5, or straight chain or branched chain alkyl,
alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or
alkoxycarbonyloxy with 1 to 20 C atoms, wherein one or more H atoms
are optionally replaced by F or C, --CN or straight chain or
branched chain alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl,
alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 6 C atoms; R.sup.xx
and R.sup.yy independently of each other denote H or alkyl with 1
to 12 C-atoms; Y.sup.01 and Y.sup.02 each, independently of one
another, denote H, alkyl having 1 to 12 C atoms, aryl, F, C, or CN;
and k and l are each and independently 0, 1, 2, 3 or 4.
2. A polymerizable mixture according to claim 1, wherein the spacer
groups Sp are selected from the formula Sp'--X', so that the
radical "P.sup.1-Sp.sup.1-" corresponds to the formula
"P.sup.1-Sp'--X'--", wherein: Sp' denotes (a) straight chain or
branched chain alkylene having 1 to 40, preferably 1 to 30 C atoms,
which is optionally mono- or polysubstituted by F, Cl, Br, I or CN
and in which, in addition, one or more non-adjacent CH.sub.2 groups
may each be replaced, independently of one another, by --O--,
--S--, --NH--, --NR.sup.01--, --SiR.sup.01R.sup.02--, --CO--,
--COO--, --OCO--, --OCO--O--, --S--CO--, --CO--S--,
--NR.sup.01--CO--O--, --O--CO--NR.sup.01--,
--NR.sup.01--CO--NR.sup.01--, --CH.dbd.CH-- or --C.ident.C-- in
such a way that O and/or S atoms are not linked directly to one
another, or (b) -Sp.sup.x-G-Sp.sup.y-, wherein Sp.sup.x and
Sp.sup.y denote independently of each other alkylene having 1 to 20
C atoms or a single bond; G denotes cycloalkylene having 3 to 20 C
atoms which is optionally mono- or polysubstituted by alkyl having
1 to 20 C atoms; X' denotes --O--, --S--, --CO--, --COO--, --OCO--,
--O--COO--, --CO--NR.sup.01--, --NR.sup.01--CO--,
--NR.sup.01--CO--NR.sup.01--, --OCH.sub.2--, --CH.sub.2O--,
--SCH.sub.2--, --CH.sub.2S--, --CF.sub.2O--, --OCF.sub.2--,
--CF.sub.2S--, --SCF.sub.2--, --CF.sub.2CH.sub.2--,
--CH.sub.2CF.sub.2--, --CF.sub.2CF.sub.2--, --CH.dbd.N--,
--N.dbd.C--, --N.dbd.N--, --CH.dbd.CR.sup.01--,
--CY.sup.01=CY.sup.02--, --C.ident.C--, --CH.dbd.CH--COO--,
--OCO--CH.dbd.CH-- or a single bond; R.sup.01 and R.sup.02 each,
independently of one another, denote H or alkyl having 1 to 12 C
atoms; and Y.sup.01 and Y.sup.02 each, independently of one
another, denote H, F, C.sub.1 or CN.
3. A polymerizable mixture according to claim 1, wherein the spacer
groups Sp are selected from the list consisting of
--(CH.sub.2).sub.p1--,
--(CH.sub.2CH.sub.2O).sub.q1--CH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2--S--CH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2--NH--CH.sub.2CH.sub.2--,
--(SiR.sup.01R.sup.02--O).sub.1
(CH.sub.2).sub.p1-(cyclo-C.sub.6H.sub.8R.sup.01R.sup.02)--(CH.sub.2).sub.-
p1--, and ##STR00057## wherein: p1 is an integer from 1 to 60; q1
is an integer from 1 to 12; and R.sup.01 and R.sup.02 each,
independently of one another, denote H or alkyl having 1 to 12 C
atoms.
4. A polymerizable mixture according to claim 1, wherein A.sup.21
to A.sup.23 denote independently and, in case of multiple
occurrence, independently of one another, a moiety selected from
the following groups a) to e): a) trans-1,4-cyclohexylene,
1,4-cyclohexenylene and 4,4'-bicyclohexylene, in which one or more
non-adjacent CH.sub.2 groups may be replaced by --O-- and/or --S--
and wherein one or more H atoms may be replaced by a group L; b)
1,4-phenylene, 1,3-phenylene, 4,4'-biphenylene, 2,5-thiphene and
2,6-dithieno[3,2-b:2',3'-d]thiophene in which one or two CH groups
may be replaced by N and where one or more H atoms may be replaced
by a group L; c) tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl,
tetrahydrofuran-2,5-diyl, cyclobut-1,3-diyl, piperidine-1,4-diyl,
thiophene-2,5-diyl and selenophen-2,5-diyl, which may be
substituted one or more groups L; d) saturated, partially
unsaturated or completely unsaturated, and optionally substituted,
polycyclic radicals having 5 to 20 cyclic C atoms, of which one or
more can also be replaced by heteroatoms, preferably selected from
the group consisting of bicyclo [1.1.1] pentane-1,3-diyl, bicyclo
[2.2.2] octane-1,4-diyl, spiro [3.3] heptane-2,6-diyl, ##STR00058##
##STR00059## where one or more H atoms may be replaced by a group
L, and/or one or more double bonds may be replaced by single bonds,
and/or one or more CH groups may be replaced by N, and where M
denotes --O--, --S--, --CH.sub.2--, --CHY.sup.03-- or
--CY.sup.03Y.sup.04--; Y.sup.03, Y.sup.04 denote independently of
each other one of the meanings given above for R.sup.01, F, Cl, CN,
OCF.sub.3 or CF.sub.3, and preferably H, F, C, CN, OCF.sub.3 or
CF.sub.3; W.sup.5, W.sup.6 denote independently of each other
--CH.sub.2CH.sub.2--, --CH.dbd.CH--, --CH.sub.2--O--,
--O--CH.sub.2--, --C(R.sup.cR.sup.d)-- or --O--; R.sup.c, R.sup.d
denote independently of each other H or alkyl having 1 to 6 C
atoms, preferably H, methyl or ethyl; and R.sup.03, R.sup.04 denote
independently of each other H, F, straight chain or branched chain
alkyl having 1 to 12 C atoms where one or more H atoms may be
replaced by F; e) cyclic imides selected from the group consisting
of: ##STR00060## where one or more H atoms may be replaced by a
group L, and/or one or more double bonds may be replaced by single
bonds, and/or one or more CH groups may be replaced by N.
5. A polymerizable mixture according to claim 1, wherein the second
monomer is one or more bi- or multifunctional compound selected
from organic compounds, polyhedralsilsesquioxane compounds and
functionalized inorganic nanoparticles.
6. A polymerizable mixture according to claim 1, wherein the second
monomer is one or more bi- or multifunctional compound comprising
two or more polymerizable groups (P) which are selected from groups
containing a C.dbd.C double bond, which preferably react with
P.sup.1 in a radical or ionic chain polymerization or in a 2+2
cycloaddition, groups containing two conjugated C.dbd.C double
bonds, which preferably react with P.sup.1 in a 4+2 cycloaddition,
nucleophilic groups, which preferably react with P.sup.1 in a
nucleophilic addition, and 1,3-dipolar groups, which preferably
react with P.sup.1 in a 1,3-dipolar cycloaddition.
7. A polymerizable mixture according to claim 1, wherein the second
monomer is one or more bi- or multifunctional compound comprising
two or more polymerizable groups (P) which are selected from groups
containing a C.dbd.C double bond, which preferably react with
P.sup.1 in a radical or ionic chain polymerization or in a 2+2
cycloaddition, groups containing two conjugated C.dbd.C double
bonds, which preferably react with P.sup.1 in a 4+2 cycloaddition,
nucleophilic groups, which preferably react with P.sup.1 in a
nucleophilic addition, and 1,3-dipolar groups, which preferably
react with P.sup.1 in a 1,3-dipolar cycloaddition and wherein the
second monomer is one or more of: (a) an organic compound
represented by Formula (4): ##STR00061## wherein: Q denotes a
hydrocarbon group having 1 to 50 carbon atoms which may be
optionally substituted with one or more substituents L, wherein L
is defined as in claim 1, and which may optionally contain one or
more hetero atom groups selected from N, O and S; P.sup.2 denotes a
polymerizable group (P); and x is an integer from 2 to 10; (b) a
polyhedralsilsesquioxane compound represented by the following
structure: ##STR00062## wherein: R is H, C.sub.1-C.sub.6-alkyl,
C.sub.2-C.sub.6-alkenyl, C.sub.6-C.sub.10-aryl, or
C.sub.1-C.sub.6-alkoxy; L is C.sub.1-C.sub.12-alkylene or
C.sub.1-C.sub.12-oxyalkylene, wherein one or more non-adjacent C
atoms may be replaced, independently of one another, by
--SiR.sup.05R.sup.06--, wherein R.sup.05 and R.sup.06 each,
independently of one another, denote H or alkyl having 1 to 6 C
atoms; P.sup.2 denotes a polymerizable group (P); y is an integer
from 6 to 12; and x is an integer from 2 to 12, wherein
y-x.gtoreq.0; or (c) a functionalized inorganic nanoparticle which
comprises polymerizable groups P.sup.2 on its surface, wherein:
P.sup.2 denotes a polymerizable group (P).
8. A method for forming a copolymer comprising the following steps:
(i) providing a polymerizable mixture according to claim 1; and
(ii) polymerizing said polymerizable mixture to obtain a
copolymer.
9. A method for forming a copolymer according to claim 8, wherein
the polymerizable mixture further comprises one or more radical
initiators.
10. A copolymer, obtainable by the method for forming a copolymer
according to claim 8.
11. A copolymer comprising at least one repeating unit which is
derived from the first monomer and at least one repeating unit
which is derived from the second monomer as defined in claim 1.
12. A copolymer comprising at least one repeating unit which is
derived from the first monomer and at least one repeating unit
which is derived from the second monomer as defined in claim 1, and
wherein the repeating unit derived from the first monomer comprises
a structural unit represented by Formula (5):
[-Sp.sup.1-(MG-Sp.sup.1).sub.m-] Formula (5) wherein Sp.sup.1, MG
and m are defined as in claim 1.
13. An electronic device comprising a copolymer according to claim
10.
14. An electronic device according to claim 13, wherein the
copolymer forms a dielectric layer.
15. A method for preparing a packaged microelectronic structure, in
which a substrate is provided with a dielectric layer, wherein the
method comprises the following steps: (1) applying a polymerizable
mixture according to claim 1 to a surface of a substrate; and (2)
curing said polymerizable mixture to form a dielectric layer.
16. A method for preparing a packaged microelectronic structure
according to claim 15, wherein the polymerizable mixture further
comprises one or more radical initiators.
17. A microelectronic device comprising a packaged microelectronic
structure obtainable by the manufacturing method according to claim
15.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a novel class of copolymers
which can be used as dielectric material for the preparation of
passivation layers in packaged electronic devices. The copolymers
are obtained from a polymerizable mixture comprising a first
monomer and a second monomer, wherein the first monomer is one or
more polymerizable 3-substituted or 3,4-disubstituted maleimide
compound having mesogenic groups and wherein the second monomer is
one or more bi- or multifunctional compound capable of reacting
with the first monomer to give a copolymer. The first monomer may
be also referred to as reactive mesogen (RM). The copolymers
obtained therefrom are thus materials with liquid-crystalline
features conserved in their structure and they provide excellent
film forming capability, excellent thermal properties, excellent
mechanical properties as well as easy processing from conventional
solvents. In particular, the copolymers are characterized by a low
dielectric constant and thermomechanical properties which reduce
thermally induced stress owing to the coefficient of thermal
expansion (CTE) mismatch between silicon (3 ppm/K) and
copper-dominated (16.5 ppm/K) substrate and package. Furthermore,
the copolymers provide a favorable and well-balanced relationship
between stiffness and elasticity so that thermal stress can be
easily compensated.
[0002] Beyond that, they are photostructurable and particularly
suitable for various applications in electronic packaging such as
e.g. the passivation of conductive or semiconducting components and
die attach and as a major component in the preparation of
substrates for printed circuit boards.
[0003] There is further provided a method for forming said
copolymers and an electronic device containing said copolymers as
dielectric material. Beyond that, the present invention relates to
a manufacturing method for preparing a packaged microelectronic
structure, wherein a dielectric copolymer layer is formed from said
polymerizable mixture, and to a microelectronic device comprising
said packaged microelectronic structure which is obtained or
obtainable by said manufacturing method.
[0004] The manufacturing method according to the present invention
allows a cost-effective and reliable manufacturing of
microelectronic devices where the number of defective products
caused by mechanical deformation (warping) due to undesirable
thermal expansion is significantly reduced. Polymerization and/or
curing can occur at significantly lower temperatures and thus
leading to lower thermal stress during manufacturing, which reduces
the waste of defective microelectronic devices, thereby allowing a
resource-efficient and sustainable production.
BACKGROUND OF THE INVENTION
[0005] Reactive mesogens (RMs), when polymerized at temperatures at
which they exhibit thermotropic liquid crystal (LC) phases
(typically nematic, cholesteric or smectic), give anisotropic
polymers which conserve the liquid crystalline state. In
particular, optical anisotropy has been widely exploited in the
field of optical films for compensation and brightness enhancement
in flat panel displays, especially in liquid crystal displays.
[0006] In addition to their wide use in liquid crystal displays and
displays, liquid crystalline materials are investigated for their
advantages in other application types due to their special physical
properties (R. Stannarius, Nat. Mat. 2009, 8, 617-618; and J. P. F.
Lagerwall et al., Current Appl. Phys. 2012, 12, 1387-1412). In
particular, highly ordered anisotropic polymer networks are an
interesting material class with a diverse range of applications (D.
J. Broer et al., Lagmuir 2014, 30, 13499-13509; and R. Zentel et
al., Adv. Mater. 2010, 22, 3366-3387). However, in most cases the
LC polymers or corresponding monomers from which the polymers are
made do not have optimum properties required for the respective
application.
[0007] WO 2012/152409 A1 relates to polymer particles with optical
anisotropy and shape anisotropy comprising monomer units of at
least one reactive mesogen, a process for their preparation, the
use of these particles for the preparation of optical,
electrooptical, electronic, electrochemical, electrophotographic,
electrowetting and electrophoretic displays and/or devices and
security, cosmetic, decorative, and diagnostic applications, and
electrophoretic fluids and displays comprising said polymer
particles. In particular, the polymer particles have monomer units
of at least one RM with at least two polymerizable groups, at least
one polymerizable dye as comonomer, optionally at least one
comonomer, optionally at least one cross-linking comonomer,
optionally at least one ionic comonomer, and optionally at least
one polymerizable stabilizer.
[0008] Various processes for the preparation of liquid-crystalline
polymers from RMs and for the preparation of the RM starting
materials are known from the state of the art. For example,
Siemensmeyer et al. describes a process for producing mixtures of
LC compounds, wherein at least one of the starting components
consists of a mixture of at least two compounds and this mixture is
reacted with at least one other starting component to form a
statistic mixture (WO 96/04351 A1).
[0009] In addition to efficient preparation methods for LC
compounds, suitable polymerization methods for forming anisotropic
polymer networks are in the focus of interest. A variety of
reactive functional groups were investigated for their
applicability in photoinitiated polymerization reactions. The most
widespread reactive functional groups are acrylates and
methacrylates, which are particularly well suited for UV-induced
free-radical polymerizations due to their high polymerization rate
(D. J. Broer et al., Lagmuir 2014, 30, 13499-13509). However, UV
curing is not suitable for all kinds of application.
[0010] Mixtures of polymerizable liquid-crystalline monomers
(reactive mesogens) can be used to prepare thin films which can be
cured by thermal or photoinitiated polymerization. Films which are
prepared in this way are relatively thin and contain a highly
cross-linked duroplastic polymer which has a pronounced dimensional
stability. However, these films are relatively brittle and exhibit
very low elasticity. If, on the other hand, the crosslinking degree
is reduced, no dimensionally stable polymer films can be
obtained.
[0011] U.S. Pat. No. 6,261,481 B1 describes an organic insulating
composition which provides a good thermal conductivity. The
insulating composition contains a liquid crystal (LC) resin
comprising a polymerization product of a resin composition
containing a monomer which has a mesogenic group. The composition
has a thermal conductivity in directions mutually orthogonal to
each other of .gtoreq.0.4 W/mK. The monomer contained in the resin
composition has a mesogenic group and preferably an epoxy group
which can be polymerized thermally under acid catalysis.
Preferably, the resin composition is heated under conditions that
the monomer having the mesogenic group is partially arranged when
the polymerization starts so that the anisotropic properties based
on the partial arrangement are frozen in the polymer.
[0012] US 2008/0075961 A1 and US 2017/0152418 A1 relate to
maleimide adhesive films which are prepared from thermosetting
maleimide resins containing imide-extended mono-, bis- and
polymaleimide compounds. The maleimide adhesive films are
photostructurable and suitable for the production of electronic
equipment, integrated circuits, semiconductor devices, passive
devices, solar batteries, solar modules, and/or light emitting
diodes. However, the maleimide compounds do not contain any
mesogenic groups which could impart a preferential direction or
partial arrangement of the compound in the film. This results in
poorer properties with regard to mechanical stability and thermal
conductivity. These materials typically also exhibit a relatively
low glass transition point, which again impact their thermal
expansion properties.
[0013] KR 20160052234 A describes a photocurable insulating resin
composition and printed circuit board using the same. The
photocurable insulating resin composition comprises a photocurable
liquid crystal oligomer; a photocurable graphene oxide; and a
photocurable metal alkoxide. However, the photocurable liquid
crystal oligomers do not contain multiple mesogenic groups linked
together by a spacer group. This results in an unfavorable
solubility profile and energies used for photocuring are very
high.
[0014] Electronic Packaging
[0015] As solid-state transistors started to replace vacuum-tube
technology, it became possible for electronic components, such as
resistors, capacitors, and diodes, to be mounted directly by their
leads into printed circuit boards of cards, thus establishing a
fundamental building block or level of packaging that is still in
use. Complex electronic functions often require more individual
components than can be interconnected on a single printed circuit
card. Multilayer card capability was accompanied by development of
three-dimensional packaging of daughter cards onto multilayer
mother boards. Integrated circuitry allows many of the discrete
circuit elements such as resistors and diodes to be embedded into
individual, relatively small components known as integrated circuit
chips or dies. In spite of incredible circuit integration, however,
more than one packaging level is typically required, in part
because of the technology of integrated circuits itself. Integrated
circuit chips are quite fragile, with extremely small terminals.
First-level packaging achieves the major functions of mechanically
protecting, cooling, and providing capability for electrical
connections to the delicate integrated circuit. At least one
additional packaging level, such as a printed circuit card, is
utilized, as some components (high-power resistors, mechanical
switches, capacitors) are not readily integrated onto a chip. For
very complex applications, such as mainframe computers, a hierarchy
of multiple packaging levels is required.
[0016] As a consequence of Moore's law, advanced electronic
packaging strategies are playing an increasingly important role in
the development of more powerful electronic products. In other
words, as the demand for smaller, faster, and more functional
mobile and portable electronic devices increases, the demand for
improved cost-effective packaging technologies is also
increasing.
[0017] A wide variety of advanced packaging technologies exist to
meet the requirements of today's semiconductor industry. The
leading Advanced Packaging technologies--wafer-level packaging
(WLP), fan-out wafer level packaging (FOWLP), 2.5D interposers,
chip-on-chip stacking, package-on-package stacking, embedded
IC--all require structuring of thin substrates, redistribution
layers and other components like high resolution inter-connects.
The end consumer market presents constant push for lower prices and
higher functionality on ever smaller and thinner devices. This
drives the need for the next generation packaging with finer
features and improved reliability at a competitive manufacturing
cost.
[0018] Wafer-level packaging (WLP) is the technology of packaging
an integrated circuit while still part of the wafer, in contrast to
the more conventional chip scale packaging method, where the wafer
is sliced into individual circuits (dices) and then packaged. WLP
offers several major advantages compared to chip scale package
technologies and it is essentially a true chip-scale package (CSP)
technology, since the resulting package is practically of the same
size as the die. Wafer-level packaging allows integration of wafer
fab, packaging, test, and burn-in at wafer level in order to
streamline the manufacturing process undergone by a device from
silicon start to customer shipment. Major application areas of WLP
are smartphones and wearables due to their size constraints.
Functions provided WLPs in smartphones or wearables include:
compass, sensors, power management, wireless etc. Wafer-level chip
scale packaging (WL-CSP) is one of the smallest packages currently
available on the market. WLP can be categorized into fan-in and
fan-out WLP (FIG. 1). Both of them use a redistribution technology
to form the connections between chips and solder balls.
[0019] Fan-out wafer level packaging (FOWLP) is one of the latest
packaging trends in microelectronics: FOWLP has a high
miniaturization potential both in the package volume as well as in
the packaging thickness. Technological basis of FOWLP is a
reconfigured, painted wafer with embedded chips and a thin film
rewiring layer, which together form a surface-mounted device
(SMD)-compatible package. The main advantages of the FOWLP are a
very thin, because substrateless package, the low thermal
resistance, good high-frequency properties due to short and planar
electrical connections together with a bumpless chip connection
instead of e.g. wire bonds or solder contacts.
[0020] With current materials, WLP processes are limited to medium
chip size applications. The reasons for this restriction are mainly
due to the current material selection, which shows a thermal
mismatch with the silicon die (CTE: 3 ppm/K) and therefore can
reduce the performance and generate stress on the dies. New
materials with better physical properties (in particular, a
coefficient of thermal expansion (CTE) closer to the CTE of silicon
together with high mechanical flexibility) are in high demand.
Currently, redistribution layers (RDLs) are made from copper layers
(CTE: 16.5 ppm/K), which are electroplated on polymer passivation
layers such as polyimides (PI), butylcyclobutanes (BCB), or
polybenzoxazoles (PBO). Low curing temperatures in addition to
photopaternability are two further important requirements in the
processing of such materials.
[0021] Polyimide became the standard passivation layer for memory
chips and other devices with the need of surface protection for the
handling and testing procedure. Photosensitive resins have been
developed to reduce processing costs.
[0022] Polyimide-ODA was the first member of a series of new high
performance polymers based on alternate aromatic homocyclic and
heterocyclic rings developed by Du Pont:
##STR00001##
[0023] Polyimides are quite unique to their very high decomposition
temperature which can go up to over 400.degree. C. In addition,
their mechanical properties guarantee a high flexibility
(elongation at break up to 100%) with a very high tensile strength
of over 200 MPa. PI is still the most popular polymer for IC
passivation.
[0024] A modification to the negative-sensitive polymer PI was
achieved by polybenzoxazole (PBO) which is sometime also called a
positive-sensitive PI:
##STR00002##
[0025] The polymer film can be developed after photo-exposure using
an aqueous developer.
[0026] The so-called BCB (benzocyclobutene) is an example of a
siloxane-polymer group having in addition a vinyl and a
benzocyclobutene ring system:
##STR00003##
[0027] A major advantage is the polymerization reaction
(Diels-Alder reaction) which has high atomic economy, since no
by-products occur. This highly-crosslinked thermoset polymer has
excellent electrical performance, but is quite brittle with a low
elongation to break value (8%) and low tensile strength of 87
MPa.
[0028] Another approach from the state of the art are
imide-extended bismaleimide resins which were suggested in US
2008/0075961 A1 and US 2017/0152418 A1. They show promising results
with regard to low-stress wafer passivation coatings. However,
despite some improvement, there is still some room for improvement
in order to meet the demanding requirements of industry.
[0029] In conclusion, the materials known from the state of the art
show the following drawbacks: [0030] Polyimides and
polybenzoxazoles typically require very high processing
temperatures which increase the risk for warping, especially in
multilayer redistribution layers (RDLs). In addition to that,
polyimides show a high water uptake which is a problem for
reliability of the devices. [0031] Benzocyclobutene derivatives as
well as polynorbornenes show a very low dielectric constant, but
this advantage is compromised by very poor adhesion to metals.
[0032] Imide-extended bismaleimide resins so far do not show a
favorable combination of advantageous mechanical and thermal
properties. They are either flexible (low modulus), but have high
CTE values, or they are brittle (high modulus) with low CTE
values.
[0033] Hence, there is a continuous need to develop new dielectric
materials which do not show the above-mentioned disadvantages known
from the prior art.
[0034] Photolithography
[0035] Photolithography has long been the key patterning technology
for structuring inorganic and organic materials used in advanced
packaging applications like flip-chip wafer bumping, electroplated
gold, solder bumps, copper pillar technologies and redistribution
layers. Photolithography is a key manufacturing process and cost
contributor; the careful selection of the right exposure solution
is critical to achieve the best possible cost structure in today's
industrial lithography applications.
[0036] Current drivers and trends in the semiconductor industry
clearly show that performance improvements of microelectronic
devices are needed to meet the future end user requirements. For
example, consumer electronic devices like tablets and smartphones
are getting thinner and smaller while gaining higher computing
power, increased data storage, and improved communication
capabilities. In addition, cost considerations become more and more
important in the competitive landscape for all parties within the
supply chain, from the chip manufacturers, foundries, assembly and
test suppliers to the device manufacturers. Therefore, the industry
strives for innovative approaches to lower manufacturing costs
coupled with enabling technologies that meet the challenging
technical requirements.
[0037] For decades, photolithography has been and still is the
fundamental process used in the fabrication and packaging of
microelectronic devices. A key component of any photolithography
process is the exposure tool, which uses light in the ultraviolet
wavelength range to pattern a photosensitive resist or polymer. The
exposure tool must be able to precisely create the desired features
and align them to the previously fabricated structures in the
underlying layers. Several types of exposure technologies exist
today: proximity or contact printing, laser direct imaging, and
projection lithography. The corresponding equipment toolsets differ
in terms of technical capability (optical resolution, overlay
performance and effective throughput), and the costs related to the
exposure process. (see H. Hichri et al., SOSS Micro Tec Photonic
System Inc., Corona, Calif., USA).
Object of the Invention
[0038] It is an object of the present invention to overcome the
deficiencies and drawbacks in the prior art and to provide a new
class of material which can be used as versatile dielectric
material in various electronic packaging applications.
[0039] Moreover, it is an object of the present invention to
provide a new class of dielectric material which shows excellent
film forming capabilities, excellent thermal properties, such as
e.g. a low coefficient of thermal expansion (CTE), and excellent
mechanical properties, such as e.g. excellent flexibility, when
used for the formation of passivation layers in packaged electronic
devices. It is a further object of the present invention to provide
a new class of dielectric material which allows easy processing
from conventional solvents.
[0040] More specifically, it is an object of the present invention
to match the coefficient of thermal expansion of the dielectric
with the thermal expansion coefficient of e.g. silicon (Si: 3
ppm/K) or copper (Cu: 16.5 ppm/K) without adversely affecting the
mechanical properties such as eg. elongation at break after UV or
thermal curing at temperatures below 200.degree. C.
[0041] Moreover, it is an object of the present invention to
provide a novel class of material which is photostructurable and
particularly suitable for various applications in electronic
packaging such as e.g. the passivation of conductive or
semiconducting components and die attach and as a major component
in the preparation of substrates for printed circuit boards. An
important field of application is the use as dielectric material
for the structuring of RDLs in packaged microelectronic
devices.
[0042] It is a further object of the present invention to provide a
polymerizable mixture from which the novel material is made of.
Beyond that, it is an object of the present invention to provide a
method for forming said novel material using the polymerizable
mixture. Finally, it is an object of the present invention to
provide an electronic device comprising said novel material as
dielectric material, a manufacturing method for preparing a
packaged microelectronic structure and a microelectronic device
comprising said packaged microelectronic structure which is
obtainable by said manufacturing method.
SUMMARY OF THE INVENTION
[0043] The present inventors have surprisingly found that the above
objects are achieved by a copolymer which is obtained from a
polymerizable mixture comprising a first monomer and a second
monomer, wherein the first monomer is one or more compound
represented by Formula (1), and wherein the second monomer is one
or more bi- or multifunctional compound capable of reacting with
the first monomer to give a copolymer:
P.sup.1--Sp.sup.1-(MG-Sp.sup.1).sub.m--P.sup.1 Formula (1)
[0044] wherein:
[0045] m is an integer from 1 to 60,
[0046] P.sup.1 denotes
##STR00004##
wherein V.sup.1 is H, and V.sup.2 is alkyl with 1 to 6 carbon
atoms, F, Cl or CN; or V.sup.1 and V.sup.2 are independently of one
another alkyl with 1 to 6 carbon atoms, F, Cl or CN;
[0047] Sp.sup.1 denotes at each occurrence a spacer group (Sp) or a
single bond;
[0048] MG is a rod-shaped mesogenic group, which is preferably
selected from Formula (2):
-(A.sup.21-Z.sup.21).sub.k-A.sup.22-(Z.sup.22-A.sup.23).sub.l-
Formula (2)
[0049] wherein:
[0050] A.sup.21 to A.sup.23 are independently and at each
occurrence independently of one another an aryl group, heteroaryl
group, heterocyclic group, alicyclic group or cyclic imide group
optionally being substituted by one or more identical or different
groups L;
[0051] Z.sup.21 and Z.sup.22 are independently and at each
occurrence independently from each other, --O--, --S--, --CO--,
--COO--, --OCO--, --S--CO--, --CO--S--, --O--COO--,
--CO--NR.sup.01--, --NR.sup.01--CO--, --NR.sup.01--CO--NR.sup.02,
--NR.sup.01--CO--O--, --O--CO--NR.sup.01--, --OCH.sub.2--,
--CH.sub.2O--, --SCH.sub.2--, --CH.sub.2S--, --CF.sub.2O--,
--OCF.sub.2--, --CF.sub.2S--, --SCF.sub.2--, --CH.sub.2CH.sub.2--,
--(CH.sub.2).sub.4--, --CF.sub.2CH.sub.2--, --CH.sub.2CF.sub.2--,
--CF.sub.2CF.sub.2--, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--,
--CH.dbd.CR.sup.01--, --CY.sup.01=CY.sup.02--, --C.ident.C--,
--CH.dbd.CH--COO--, --OCO--CH.dbd.CH--, or a single bond;
[0052] R.sup.01 and R.sup.02 each, independently of one another,
denote H or alkyl having 1 to 12 C atoms;
[0053] L is F, Cl, Br, I, --CN, --NO.sub.2, --NCO, --NCS, --OCN,
--SCN, --C(.dbd.O)NR.sup.xxR.sup.yy, --C(.dbd.O)OR.sup.xx,
--C(.dbd.O)R.sup.xx, --NR.sup.xxR.sup.yy, --OH, --SF.sub.5, or
straight chain or branched chain alkyl, alkoxy, alkylcarbonyl,
alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 20
C atoms, wherein one or more H atoms are optionally replaced by F
or Cl, --CN or straight chain or branched chain alkyl, alkoxy,
alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or
alkoxycarbonyloxy with 1 to 6 C atoms;
[0054] R.sup.xx and R.sup.yy independently of each other denote H
or alkyl with 1 to 12 C-atoms;
[0055] Y.sup.01 and Y.sup.02 each, independently of one another,
denote H, alkyl having 1
[0056] to 12 C atoms, aryl, F, Cl, or CN; and
[0057] k and l are each and independently 0, 1, 2, 3 or 4.
[0058] Said polymerizable mixtures are used as starting material to
form a new class of copolymers which exhibit a low thermal
expansion and at the same time show high mechanical flexibility.
Said copolymers are prepared by the following method which also
forms part of the present invention:
[0059] Method for forming a copolymer, wherein the method comprises
the following steps:
[0060] (i) providing a polymerizable mixture according to the
present invention; and
[0061] (ii) polymerizing said polymerizable mixture to obtain a
copolymer.
[0062] Moreover, a copolymer is provided which is obtainable or
obtained by the above-mentioned method for forming a copolymer.
[0063] Beyond that, an electronic device is provided comprising a
copolymer according to the present invention.
[0064] Finally, a manufacturing method for preparing a packaged
microelectronic structure is provided, in which a substrate is
provided with a dielectric layer, wherein the method comprises the
following steps: [0065] (1) applying a polymerizable mixture
according to the present invention to a surface of a substrate; and
[0066] (2) polymerizing said polymerizable composition to form a
dielectric layer.
[0067] There is also provided a microelectronic device comprising a
packaged microelectronic structure which is obtainable or obtained
by the manufacturing method according to the present invention.
[0068] Preferred embodiments of the present invention are described
hereinafter and in the dependent claims.
BRIEF DESCRIPTION OF THE FIGURES
[0069] FIG. 1: Cross-sectional view of fan-in and fan-out WLP with
die (1) and fan-out area (2).
DETAILED DESCRIPTION
Definitions
[0070] The term "liquid crystal", "mesomorphic compound", or
"mesogenic compound" (also shortly referred to as "mesogen") means
a compound that under suitable conditions of temperature, pressure
and concentration can exist as a mesophase or in particular as a LC
phase. Non-amphiphilic mesogenic compounds comprise for example one
or more calamitic, banana-shaped or discotic mesogenic groups.
[0071] The term "calamitic" means a rod-or board/lath-shaped
compound or group. The term "banana-shaped" means a bent group in
which two, usually calamitic, mesogenic groups are linked through a
semi-rigid group in such a way as not to be co-linear. The term
"discotic" means a disc- or sheet-shaped compound or group.
[0072] The term "mesogenic group" or its abbreviation "MG" means a
group with the ability to induce liquid crystal (LC) phase
behavior. Mesogenic groups, especially those of the non-amphiphilic
type, are usually either calamitic or discotic. The compounds
comprising mesogenic groups do not necessarily have to exhibit an
LC phase themselves. It is also possible that they show LC phase
behavior only in mixtures with other compounds, or when the
mesogenic compounds or the mixtures thereof are polymerized. For
the sake of simplicity, the term "liquid crystal" is used
hereinafter for both mesogenic and LC materials.
[0073] A calamitic mesogenic compound is usually comprising a
calamitic, i.e. rod-or lath-shaped, mesogenic group consisting of
one or more aromatic or alicyclic groups connected to each other
directly or via linkage groups, optionally comprising terminal
groups attached to the short ends of the rod, and optionally
comprising one or more lateral groups attached to the long sides of
the rod, wherein these terminal and lateral groups are usually
selected e.g. from carbyl or hydrocarbyl groups, polar groups like
halogen, nitro, hydroxy, etc., or polymerizable groups.
[0074] A discotic mesogenic compound is usually comprising a
discotic, i.e. relatively flat disc- or sheet-shaped mesogenic
group consisting for example of one or more condensed aromatic or
alicyclic groups, like for example triphenylene, and optionally
comprising one or more terminal groups that are attached to the
mesogenic group and are selected from the terminal and lateral
groups mentioned above.
[0075] The term "reactive mesogen" or its abbreviation "RM" means a
polymerizable mesogenic or liquid crystalline compound, which is
preferably a monomeric or oligomeric compound.
[0076] The term "spacer" or "spacer group", also referred to as
"Sp" below, is known to the person skilled in the art and is
described in the literature.
[0077] Unless stated otherwise, the term "spacer" or "spacer group"
above and below denotes a flexible organic group, which in a
polymerizable mesogenic compound ("RM") connects the mesogenic
group and the polymerizable group(s).
[0078] The term "polymer" includes, but is not limited to,
homopolymers, copolymers, for example, block, random, and
alternating copolymers, terpolymers, quaterpolymers, etc., and
blends and modifications thereof. Furthermore, unless otherwise
specifically limited, the term "polymer" shall include all possible
configurational isomers of the material. These configurations
include, but are not limited to isotactic, syndiotactic, and
atactic symmetries. A polymer is a molecule of high relative
molecular mass, the structure of which essentially comprises the
multiple repetition of units (i.e. repeating units) derived,
actually or conceptually, from molecules of low relative mass (i.e.
monomers). In the context of the present invention polymers are
composed of more than 60 monomers.
[0079] The term "oligomer" is a molecular complex that consists of
a few monomer units, in contrast to a polymer, where the number of
monomers is, in principle, unlimited. Dimers, trimers and tetramers
are, for instance, oligomers composed of two, three and four
monomers, respectively. In the context of the present invention
oligomers may be composed of up to 60 monomers.
[0080] The term "monomer" as used herein refers to a polymerizable
compound which can undergo polymerization thereby contributing
constitutional units (repeating units) to the essential structure
of a polymer or an oligomer. Polymerizable compounds are
functionalized compounds having one or more polymerizable groups.
Large numbers of monomers combine in polymerization reactions to
form polymers. Monomers with one polymerizable group are also
referred to as "monofunctional" or "monoreactive" compounds,
compounds with two polymerizable groups as "bifunctional" or
"direactive" compounds, and compounds with more than two
polymerizable groups as "multifunctional" or "multireactive"
compounds. Compounds without a polymerizable group are also
referred to as "non-functional" or "non-reactive" compounds.
[0081] The term "homopolymer" as used herein stands for a polymer
derived from one species of (real, implicit or hypothetical)
monomer.
[0082] The term "copolymer" as used herein generally means any
polymer derived from more than one species of monomer, wherein the
polymer contains more than one species of corresponding repeating
unit. In one embodiment the copolymer is the reaction product of
two or more species of monomer and thus comprises two or more
species of corresponding repeating unit. It is preferred that the
copolymer comprises two, three, four, five or six species of
repeating unit. Copolymers that are obtained by copolymerization of
three monomer species can also be referred to as terpolymers.
Copolymers that are obtained by copolymerization of four monomer
species can also be referred to as quaterpolymers. Copolymers may
be present as block, random, and/or alternating copolymers.
[0083] The term "block copolymer" as used herein stands for a
copolymer, wherein adjacent blocks are constitutionally different,
i.e. adjacent blocks comprise repeating units derived from
different species of monomer or from the same species of monomer
but with a different composition or sequence distribution of
repeating units.
[0084] Further, the term "random copolymer" as used herein refers
to a polymer formed of macromolecules in which the probability of
finding a given repeating unit at any given site in the chain is
independent of the nature of the adjacent repeating units. Usually,
in a random copolymer, the sequence distribution of repeating units
follows Bernoullian statistics.
[0085] The term "alternating copolymer" as used herein stands for a
copolymer consisting of macromolecules comprising two species of
repeating units in alternating sequence.
[0086] "Electronic packaging" is a major discipline within the
field of electronic engineering, and includes a wide variety of
technologies. It refers to inserting discrete components,
integrated circuits, and MSI (medium-scale integration) and LSI
(large-scale integration) chips (usually attached to a lead frame
by beam leads) into plates through hole on multilayer circuit
boards (also called cards), where they are soldered in place.
Packaging of an electronic system must consider protection from
mechanical damage, cooling, radio frequency noise emission,
protection from electrostatic discharge maintenance, operator
convenience, and cost.
[0087] The term "microelectronic device" as used herein refers to
electronic devices of very small electronic designs and components.
Usually, but not always, this means micrometer-scale or smaller.
These devices typically contain one or more microelectronic
components which are made from semiconductor materials and
interconnected in a packaged structure to form the microelectronic
device. Many electronic components of normal electronic design are
available in a microelectronic equivalent. These include
transistors, capacitors, inductors, resistors, diodes and naturally
insulators and conductors can all be found in microelectronic
devices. Unique wiring techniques such as wire bonding are also
often used in microelectronics because of the unusually small size
of the components, leads and pads.
[0088] "Nanoparticles" as used herein are particles with a mean
diameter in the range from 1 to 100 nm. More preferably,
nanoparticles have a mean diameter in the range from 20 to 80 nm,
more preferably from 40 to 60 nm.
Preferred Embodiments
[0089] Polymerizable Compound
[0090] The present invention relates to a polymerizable mixture
comprising a first monomer and a second monomer, wherein the first
monomer is one or more compound represented by Formula (1), and
wherein the second monomer is one or more bi- or multifunctional
compound capable of reacting with the first monomer to give a
copolymer:
P.sup.1--Sp.sup.1-(MG-Sp.sup.1).sub.m--P.sup.1 Formula (1)
[0091] wherein:
[0092] m is an integer from 1 to 60;
[0093] P.sup.1 denotes
##STR00005##
wherein V.sup.1 is H, and V.sup.2 is alkyl with 1 to 6 carbon
atoms, F, Cl or CN; or V.sup.1 and V.sup.2 are independently of one
another alkyl with 1 to 6 carbon atoms, F, Cl or CN;
[0094] Sp.sup.1 denotes at each occurrence a spacer group (Sp) or a
single bond;
[0095] MG is a rod-shaped mesogenic group, which is preferably
selected from Formula (2):
-(A.sup.21-Z.sup.21).sub.k-A.sup.22-(Z.sup.22-A.sup.23).sub.l-
Formula (2)
[0096] wherein:
[0097] A.sup.21 to A.sup.23 are independently and at each
occurrence independently of one another an aryl group, heteroaryl
group, heterocyclic group, alicyclic group or cyclic imide group
optionally being substituted by one or more identical or different
groups L;
[0098] Z.sup.21 and Z.sup.22 are independently and at each
occurrence independently from each other, --O--, --S--, --CO--,
--COO--, --OCO--, --S--CO--, --CO--S--, --O--COO--,
--CO--NR.sup.01--, --NR.sup.01--CO--, --NR.sup.01--CO--NR.sup.02,
--NR.sup.01--CO--O--, --O--CO--NR.sup.01--, --OCH.sub.2--,
--CH.sub.2O--, --SCH.sub.2--, --CH.sub.2S--, --CF.sub.2O--,
--OCF.sub.2--, --CF.sub.2S--, --SCF.sub.2--, --CH.sub.2CH.sub.2--,
--(CH.sub.2).sub.4--, --CF.sub.2CH.sub.2--, --CH.sub.2CF.sub.2--,
--CF.sub.2CF.sub.2--, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--,
--CH.dbd.CR.sup.01--, --CY.sup.01=CY.sup.02--, --C.ident.C--,
--CH.dbd.CH--COO--, --OCO--CH.dbd.CH--, or a single bond;
[0099] R.sup.01 and R.sup.02 each, independently of one another,
denote H or alkyl having 1 to 12 C atoms;
[0100] L is F, Cl, Br, I, --CN, --NO.sub.2, --NCO, --NCS, --OCN,
--SCN, --C(.dbd.O)NR.sup.xxR.sup.yy, --C(.dbd.O)OR.sup.xx,
--C(.dbd.O)R.sup.xx, --NR.sup.xxR.sup.yy, --OH, --SF.sub.5, or
straight chain or branched chain alkyl, alkoxy, alkylcarbonyl,
alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 20
C atoms, wherein one or more H atoms are optionally replaced by F
or Cl, --CN or straight chain or branched chain alkyl, alkoxy,
alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or
alkoxycarbonyloxy with 1 to 6 C atoms;
[0101] R.sup.xx and R.sup.yy independently of each other denote H
or alkyl with 1 to 12 C-atoms;
[0102] Y.sup.01 and Y.sup.02 each, independently of one another,
denote H, alkyl having 1 to 12 C atoms, aryl, F, Cl, or CN; and
[0103] k and l are each and independently 0, 1, 2, 3 or 4.
[0104] Points of attachment (binding sites) of structural elements
presented in this patent application may be indicated by
##STR00006##
wherein * represents the structural element and
##STR00007##
a binding site.
[0105] The polymerizable group P.sup.1 is a 3-substituted or
3,4-disubstituted maleimide group which is capable to undergo a
polymerization reaction such as, for example, a radical or ionic
chain polymerization reaction, or a polyaddition reaction (e.g.
cycloadditions, such as 2+2 cycloadditions, 4+2 cycloadditions
(Diels-Alder reactions) or 1,3-dipolar cycloadditions, or
nucleophilic additions, such as Michael reactions), or which is
capable to undergo a polymerization analogous reaction such as, for
example, an addition to a polymer backbone by one of the
aforementioned reaction types.
[0106] It is preferred that the index m is an integer from 1 to 50,
more preferably from 2 to 30, and most preferably from 3 to 20.
[0107] It is preferred that V.sup.1 and V.sup.2 are independently
from each other selected from alkyl with 1 to 6 carbon atoms, F, Cl
or CN. It is more preferred that V.sup.1 and V.sup.2 are
independently from each other selected from alkyl with 1 to 3
carbon atoms, F, Cl or CN. Preferred alkyl with 1 to 3 carbon atoms
is methyl, ethyl and propyl. V.sup.1 and V.sup.2 may be identical
or different from each other. It is particularly preferred that
V.sup.1 and V.sup.2 are identical.
[0108] Alternatively, it is preferred that V.sup.1 is H, and
V.sup.2 is selected from alkyl with 1 to 6 carbon atoms, F, Cl or
CN, more preferably from alkyl with 1 to 3 carbon atoms, F, Cl or
CN. Preferred alkyl with 1 to 3 carbon atoms is methyl, ethyl and
propyl.
[0109] It is preferred that Z.sup.21 and Z.sup.22 are independently
and at each occurrence independently from each other --COO--,
--OCO--, --CO--O--, --O--CO--, --OCH.sub.2--, --CH.sub.2O--,
--CH.sub.2CH.sub.2--, --(CH.sub.2).sub.4--, --CF.sub.2CH.sub.2--,
--CH.sub.2CF.sub.2--, --CF.sub.2CF.sub.2--, --C.ident.C--,
--CH.dbd.CH--COO--, --OCO--CH.dbd.CH--, or a single bond.
[0110] Preferably, k and l are each and independently 0, 1 or 2,
more preferably k and l are 1.
[0111] Preferred spacer groups Sp are selected from the formula
Sp'--X', so that the radical "P.sup.1-Sp.sup.1-" corresponds to the
formula "P.sup.1-Sp'--X'--", wherein: Sp' denotes [0112] (a)
straight chain or branched chain alkylene having 1 to 40,
preferably 1 to 30, C atoms, which is optionally mono- or
polysubstituted by F, Cl, Br, I or CN and in which, in addition,
one or more non-adjacent CH.sub.2 groups may each be replaced,
independently of one another, by --O--, --S--, --NH--,
--NR.sup.01--, --SiR.sup.01R.sup.02--, --CO--, --COO--, --OCO--,
--OCO--O--, --S--CO--, --CO--S--, --NR.sup.01--CO--O--,
--O--CO--NR.sup.01--, --NR.sup.01--CO--NR.sup.01--, --CH.dbd.CH--
or --C.ident.C-- in such a way that O and/or S atoms are not linked
directly to one another, or [0113] (b) -Sp.sup.x-G-Sp.sup.y-,
wherein Sp.sup.x and Sp.sup.y denote independently of each other
alkylene having 1 to 20 C atoms, preferably 1 to 12 C atoms, or a
single bond; G denotes cycloalkylene having 3 to 20 C atoms,
preferably 5 to 12 C atoms, which is optionally mono- or
polysubstituted by alkyl having 1 to 20 C atoms, preferably 1 to 12
C atoms; [0114] X' denotes --O--, --S--, --CO--, --COO--, --OCO--,
--O--COO--, --CO--NR.sup.01, --NR.sup.01--CO--,
--NR.sup.01--CO--NR.sup.01--, --OCH.sub.2--, --CH.sub.2O--,
--SCH.sub.2--, --CH.sub.2S--, --CF.sub.2O--, --OCF.sub.2--,
--CF.sub.2S--, --SCF.sub.2--, --CF.sub.2CH.sub.2--,
--CH.sub.2CF.sub.2--, --CF.sub.2CF.sub.2--, --CH.dbd.N--,
--N.dbd.C--, --N.dbd.N--, --CH.dbd.CR.sup.01--,
--CY.sup.01=CY.sup.02--, --C.ident.C--, --CH.dbd.CH--COO--,
--OCO--CH.dbd.CH-- or a single bond, preferably --O--, --S--,
--CO--, --COO--, --OCO--, --O--COO--, --CO--NR.sup.0--,
--NR.sup.01--CO--, --NR.sup.01--CO--NR.sup.01-- or a single bond;
[0115] R.sup.01 and R.sup.02 each, independently of one another,
denote H or alkyl having 1 to 12 C atoms; and [0116] Y.sup.01 and
Y.sup.02 each, independently of one another, denote H, F, Cl or
CN.
[0117] Preferred groups Sp' are in each case selected from straight
chain methylene, ethylene, propylene, butylene, pentylene,
hexylene, heptylene, octylene, nonylene, decylene, undecylene,
dodecylene, and octadecylene, cyclo-hexylene, ethyleneoxyethylene,
methyleneoxybutylene, ethylenethioethylene,
ethylene-N-methyliminoethylene, 1-methylalkylene, ethenylene,
propenylene and butenylene.
[0118] More preferred spacer groups Sp are selected from the list
consisting of --(CH.sub.2).sub.p1--,
--(CH.sub.2CH.sub.2O).sub.q1--CH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2--S--CH.sub.2CH.sub.2--,
--CH.sub.2CH.sub.2--NH--CH.sub.2CH.sub.2--,
--(SiR.sup.01R.sup.02--O).sub.p1--,
--(CH.sub.2).sub.p1-(cyclo-C.sub.6H.sub.8R.sup.01R.sup.02)--(CH.sub.2).su-
b.p1--, and
##STR00008##
[0119] wherein:
[0120] p1 is an integer from 1 to 60, preferably from 1 to 36, more
preferably from 1 to 12; [0121] q1 is an integer from 1 to 12,
preferably from 1 to 3; and
[0122] R.sup.01 and R.sup.02 each, independently of one another,
denote H or alkyl having 1 to 12 C atoms.
[0123] Most preferred groups Sp are --(CH.sub.2).sub.p1--,
--O--(CH.sub.2).sub.p1--, --O--(CH.sub.2).sub.p1--O--,
--OCO--(CH.sub.2).sub.p1--, and --OCOO--(CH.sub.2).sub.p1--, in
which p1 is an integer from 1 to 36, preferably from 1 to 12.
[0124] In a preferred embodiment of the present invention, the
groups A.sup.21 to A.sup.23 denote independently and, in case of
multiple occurrence, independently of one another, a moiety
selected from the following groups a) to e): [0125] a)
trans-14-cyclohexylene, 1,4-cyclohexenylene and
4,4'-bicyclohexylene, in which one or more non-adjacent CH.sub.2
groups may be replaced by --O-- and/or --S-- and wherein one or
more H atoms may be replaced by a group L; [0126] b) 1,4-phenylene,
1,3-phenylene, 4,4'-biphenylene, 2,5-thiphene and
2,6-dithieno[3,2-b:2',3'-d]thiophene in which one or two CH groups
may be replaced by N and where one or more H atoms may be replaced
by a group L; [0127] c) tetrahydropyran-2,5-diyl,
1,3-dioxane-2,5-diyl, tetrahydrofuran-2,5-diyl, cyclobut-1,3-diyl,
piperidine-1,4-diyl, thiophene-2,5-diyl and selenophen-2,5-diyl,
which may be substituted one or more groups L; [0128] d) saturated,
partially unsaturated or completely unsaturated, and optionally
substituted, polycyclic radicals having 5 to 20 cyclic C atoms, of
which one or more can also be replaced by heteroatoms, preferably
selected from the group consisting of bicyclo
[1.1.1]pentane-1,3-diyl, bicyclo [2.2.2] octane-1,4-diyl, spiro
[3.3] heptane-2,6-diyl,
[0128] ##STR00009## ##STR00010## [0129] where one or more H atoms
may be replaced by a group L, and/or one or more double bonds may
be replaced by single bonds, and/or one or more CH groups may be
replaced by N, and where [0130] M denotes --O--, --S--,
--CH.sub.2--, --CHY.sup.03-- or --CY.sup.03Y.sup.04--; [0131]
Y.sup.03, Y.sup.04 denote independently of each other one of the
meanings given above for R.sup.01, F, Cl, CN, OCF.sub.3 or
CF.sub.3, and preferably H, F, Cl, CN, OCF.sub.3 or CF.sub.3;
[0132] W.sup.5, W.sup.6 denote independently of each other
--CH.sub.2CH.sub.2--, --CH.dbd.CH--, --CH.sub.2--O--,
--O--CH.sub.2--, --C(R.sup.cR.sup.d)-- or --O--; [0133] R.sup.c,
R.sup.d denote independently of each other H or alkyl having 1 to 6
C atoms, preferably H, methyl or ethyl; and [0134] R.sup.03,
R.sup.04 denote independently of each other H, F, straight chain or
branched chain alkyl having 1 to 12 C atoms where one or more H
atoms may be replaced by F; [0135] e) cyclic imides selected from
the group consisting of:
[0135] ##STR00011## [0136] where one or more H atoms may be
replaced by a group L, and/or one or more double bonds may be
replaced by single bonds, and/or one or more CH groups may be
replaced by N.
[0137] It is preferred that the first monomer comprised in the
polymerizable mixture according to the present invention is one,
two, three or four compound(s) represented by Formula (1).
[0138] Preferred compounds according to Formula (1) are:
##STR00012## ##STR00013## ##STR00014## ##STR00015## ##STR00016##
##STR00017## ##STR00018##
[0139] where the radicals and indices have the following meanings:
[0140] L is F, Cl, Br, I, --CN, --NO.sub.2, --NCO, --NCS, --OCN,
--SCN, --C(.dbd.O)NR.sup.xxR.sup.yy, --C(.dbd.O)OR.sup.xx,
--C(.dbd.O)Rx, --NR.sup.xxR.sup.yy, --OH, --SF.sub.5, or straight
chain or branched chain alkyl, alkoxy, alkylcarbonyl,
alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 20
C atoms, preferably 1 to 12 C atoms, wherein one or more H atoms
are optionally replaced by F or Cl, preferably F, --CN or straight
chain or branched chain alkyl, alkoxy, alkylcarbonyl,
alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 6 C
atoms; [0141] R.sup.xx and R.sup.yy independently of each other
denote H or alkyl with 1 to 12 C atoms; [0142] r is 0, 1, 2, 3 or
4; [0143] s is 0, 1, 2 or 3; [0144] t is 0, 1 or 2; [0145] Z.sup.21
and Z.sup.22 are independently and at each occurrence independently
from each other, --O--, --S--, --CO--, --COO--, --OCO--, --S--CO--,
--CO--S--, --O--COO--, --CO--NR.sup.01--, --NR.sup.01--CO--,
--NR.sup.01--CO--NR.sup.02, --NR.sup.01--CO--O--,
--O--CO--NR.sup.01--, --OCH.sub.2--, --CH.sub.2O--, --SCH.sub.2--,
--CH.sub.2S--, --CF.sub.2O--, --OCF.sub.2--, --CF.sub.2S--,
--SCF.sub.2--, --CH.sub.2CH.sub.2--, --(CH.sub.2).sub.4--,
--CF.sub.2CH.sub.2--, --CH.sub.2CF.sub.2--, --CF.sub.2CF.sub.2--,
--CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--, --CH.dbd.CR.sup.01--,
--CY.sup.01=CY.sup.02--, --C.ident.C--, --CH.dbd.CH--COO--,
--OCO--CH.dbd.CH--, or a single bond, preferably --COO--, --OCO--,
--CO--O--, --O--CO--, --OCH.sub.2--, --CH.sub.2O--,
--CH.sub.2CH.sub.2--, --(CH.sub.2).sub.4--, --CF.sub.2CH.sub.2--,
--CH.sub.2CF.sub.2--, --CF.sub.2CF.sub.2--, --C.ident.C--,
--CH.dbd.CH--COO--, --OCO--CH.dbd.CH--, or a single bond; [0146]
R.sup.01 and R.sup.02 each, independently of one another, denote H
or alkyl having 1 to 12 C atoms; [0147] Sp.sup.1 denotes at each
occurrence a space group (Sp) as defined above or a single bond;
[0148] P.sup.1 denotes
##STR00019##
[0148] where V.sup.1 is H, and V.sup.2 is alkyl with 1 to 6 carbon
atoms, F, Cl or CN; or V.sup.1 and V.sup.2 are independently of one
another alkyl with 1 to 6 carbon atoms, F, Cl or CN; and [0149] m
is an integer from 1 to 60, preferably from 1 to 50, more
preferably from 2 to 30, and most preferably from 3 to 20.
[0150] More preferred compounds according to Formula (1) are:
##STR00020##
[0151] where the radicals and indices have one of the meanings as
defined above.
[0152] Particularly preferred compounds according to Formula (1)
are:
##STR00021## ##STR00022##
[0153] where the radicals and indices have one of the meanings as
defined above.
[0154] Most preferred compounds according to Formula (1) are:
##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027##
##STR00028## ##STR00029## [0155] wherein [0156] n is an integer
from 1 to 60, preferably from 1 to 36, and more preferably from 6
to 12; and [0157] m is an integer from 1 to 60, preferably from 1
to 50, more preferably from 2 to 30, and most preferably from 3 to
20.
[0158] In the compounds of formulae M1 to M33 and the corresponding
sub-formulae, the ring group
##STR00030##
is preferably
##STR00031## [0159] wherein [0160] L is at each occurrence
independently from each other F, Cl, Br, I, --CN, --NO.sub.2,
--NCO, --NCS, --OCN, --SCN, --C(.dbd.O)NR.sup.xxR.sup.yy,
--C(.dbd.O)OR.sup.xx, --C(.dbd.O)R.sup.xx, --NR.sup.xxR.sup.yy,
--OH, --SF.sub.5, or straight chain or branched chain alkyl,
alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or
alkoxycarbonyloxy with 1 to 20 C atoms, preferably 1 to 12 C atoms,
wherein one or more H atoms are optionally replaced by F or Cl,
preferably F, --CN or straight chain or branched chain alkyl,
alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or
alkoxycarbonyloxy with 1 to 6 C atoms; and [0161] R.sup.xx and
R.sup.yy are defined according to the definitions given above.
[0162] The compounds represented by Formula (1) can be prepared by
any standard synthesis. Usually, the compound is retrosynthetically
cut into smaller units and formed stepwise from suitable precursor
compounds. For this purpose, known standard reactions can be used.
It has proven to be particularly advantageous to attach the
3-substituted or 3,4-disubstituted maleimide groups P.sup.1 at a
late stage of the synthesis, typically at the very last step of the
synthesis. By doing so, undesirable side-reactions or premature
polymerization of the compound can be avoided.
[0163] Preferably, a precursor represented by Formula (3):
X-Sp.sup.1-(MG-Sp.sup.1).sub.m--X Formula (3)
[0164] is reacted with
##STR00032##
[0165] to form a polymerizable compound represented by Formula
(1):
P.sup.1--Sp.sup.1-(MG-Sp.sup.1).sub.m--P.sup.1 Formula (1)
[0166] wherein X is NH.sub.2;
[0167] P.sup.1 is
##STR00033##
and V.sup.1, V.sup.2, Sp.sup.1, MG, and m have one of the
definitions as given above.
[0168] The second monomer comprised in the polymerizable mixture
according to the present invention is one or more, preferably one,
two, three or four, bi- or multifunctional compound(s) capable of
reacting with the first monomer to give a copolymer.
[0169] It is preferred that the second monomer is one or more,
preferably one, two, three or four, bi- or multifunctional
compound(s) selected from organic compounds,
polyhedralsilsesquioxane compounds and functionalized inorganic
nanoparticles.
[0170] It is further preferred that the second monomer is one or
more, preferably one, two, three or four, bi- or multifunctional
compound(s) comprising two or more polymerizable groups (P)
(reactive groups) which are selected from groups containing a
C.dbd.C double bond, which preferably react with P.sup.1 in a
radical or ionic chain polymerization or in a 2+2 cycloaddition,
groups containing two conjugated C.dbd.C double bonds, which
preferably react with P.sup.1 in a 4+2 cycloaddition (Diels-Alder
reaction), nucleophilic groups, which preferably react with P.sup.1
in a nucleophilic addition (Michael reaction), and 1,3-dipolar
groups, which preferably react with P.sup.1 in a 1,3-dipolar
cycloaddition.
[0171] Preferred groups containing a C.dbd.C double bond are
selected from:
CH.sub.2.dbd.CW.sup.1--COO--, CH.sub.2.dbd.CW.sup.1--CO--,
##STR00034##
CH.sub.2.dbd.CW.sup.2--(O).sub.k3--,
CW.sup.1.sub.2.dbd.CH--CO--(O).sub.k3--,
CW.sup.1.sub.2.dbd.CH--CO--NH--, CH.sub.2.dbd.CW.sup.1--CO--NH--,
CH.sub.3--CH.dbd.CH--O--, CH.sub.2.dbd.CH--CH.sub.2--O--,
(CH.sub.2.dbd.CH).sub.2CH--O--CO--,
(CH.sub.2.dbd.CH--CH.sub.2).sub.2CH--O--CO--,
(CH.sub.2.dbd.CH).sub.2CH--O--,
(CH.sub.2.dbd.CH--CH.sub.2).sub.2N--,
(CH.sub.2.dbd.CH--CH.sub.2).sub.2N--CO--,
CH.sub.2.dbd.CW.sup.1--CO--NH--,
CH.sub.2.dbd.CH--(CO--O).sub.k1-Phe-(O).sub.k2--,
CH.sub.2.dbd.CH--(CO).sub.k1-Phe-(O).sub.k2--, or Phe-CH.dbd.CH--;
wherein W.sup.1 denotes H, F, Cl, CN, CF.sub.3, phenyl or alkyl
having 1 to 5 C atoms,
[0172] preferably H or CH.sub.3;
[0173] W.sup.2 denotes H or alkyl having 1 to 5 C atoms, preferably
H or CH.sub.3;
[0174] W.sup.3 and W.sup.4 each, independently of one another,
denote H, Cl or alkyl having 1 to 5 C atoms, preferably H or
CH.sub.3;
[0175] Phe denotes 1,4-phenylene, which is optionally substituted
by one or more radicals L as being defined above; and
[0176] k.sub.1, k.sub.2 and k.sub.3 each, independently of one
another, denote 0 or 1; and k.sub.4 is an integer from 1 to 10.
[0177] Preferred groups containing two conjugated C.dbd.C double
bonds are selected from:
CW.sup.1.sub.2.dbd.CW.sup.1--CW.sup.1.dbd.CW.sup.1--; wherein
[0178] W.sup.1 denotes H, F, Cl, CN, CF.sub.3, phenyl or alkyl
having 1 to 5 C atoms, preferably H or CH.sub.3.
[0179] Preferred nucleophilic groups are selected from:
HS--(CH.sub.2).sub.k5--CO--(O).sub.k3--,
HS--(CH.sub.2).sub.k5--CO--, HS--(CH.sub.2).sub.k5--(O).sub.k3--,
HS--(CH.sub.2).sub.k5--O--CO--, HS--(CH.sub.2).sub.k5--CO--NH--,
HS--(CH.sub.2).sub.k5--NH--CO--, HS-Phe-(O).sub.k2--,
H.sub.2N--(CH.sub.2).sub.k5--CO--(O).sub.k3--,
H.sub.2N--(CH.sub.2).sub.k5--CO--,
H.sub.2N--(CH.sub.2).sub.k5--(O).sub.k3--,
H.sub.2N--(CH.sub.2).sub.k5--O--CO--,
H.sub.2N--(CH.sub.2).sub.k5--CO--NH--,
H.sub.2N--(CH.sub.2).sub.k5--NH--CO--, or
H.sub.2N-Phe-(O).sub.k2--; wherein
[0180] k.sub.2 and k.sub.3 each, independently of one another,
denote 0 or 1; and
[0181] k.sub.5 is an integer from 0 to 10, preferably from 0 to 5,
more preferably 0, 1 or 2.
[0182] Preferred 1,3-dipolar groups are selected from:
##STR00035## ##STR00036##
wherein:
[0183] W.sup.5 denotes at each occurrence independently from each
other H, phenyl or alkyl having 1 to 5 C atoms, preferably phenyl
or CH.sub.3.
[0184] Particularly preferred polymerizable groups (P) are selected
from:
[0185] CH.sub.2.dbd.CW.sup.1--COO--,
CH.sub.2.dbd.CW.sup.1--CO--,
##STR00037##
CH.sub.2.dbd.CW.sup.2--(O).sub.k3--,
CW.sup.1.sub.2.dbd.CH--CO--(O).sub.k3--, CH.sub.3--CH.dbd.CH--O--,
CH.sub.2.dbd.CH--CH.sub.2--O--,
HS--(CH.sub.2).sub.k5--CO--(O).sub.k3--,
HS--(CH.sub.2).sub.k5--CO--, HS--(CH.sub.2).sub.k5--(O).sub.k3--,
HS--(CH.sub.2).sub.k5--O--CO--,
H.sub.2N--(CH.sub.2).sub.k5--CO--(O).sub.k3--,
H.sub.2N--(CH.sub.2).sub.k5--CO--,
H.sub.2N--(CH.sub.2).sub.k5--(O).sub.k3--, or
H.sub.2N--(CH.sub.2).sub.k5--O--CO--; wherein
[0186] W.sup.1 denotes H, F, Cl, CN, CF.sub.3, phenyl or alkyl
having 1 to 5 C atoms, preferably H or CH.sub.3;
[0187] W.sup.2 denotes H or alkyl having 1 to 5 C atoms, preferably
H or CH.sub.3;
[0188] W.sup.3 and W.sup.4 each, independently of one another,
denote H, Cl or alkyl having 1 to 5 C atoms, preferably H or
CH.sub.3;
[0189] k.sub.3 denotes 0 or 1; and
[0190] k.sub.5 is an integer from 0 to 10, preferably from 0 to 5,
more preferably 0, 1 or 2.
[0191] Preferred organic compounds to be used as second monomer are
represented by Formula (4):
##STR00038##
[0192] wherein:
[0193] Q denotes a hydrocarbon group having 1 to 50 carbon atoms,
preferably 1 to 30 carbon atoms, which may be optionally
substituted with one or more substituents L, wherein L is as
defined above, and which may optionally contain one or more hetero
atoms selected from N, O and S;
[0194] P.sup.2 denotes a polymerizable group (P) as defined above;
and
[0195] x is an integer from 2 to 10, preferably from 2 to 4, more
preferably x=2.
[0196] As it is apparent from Formula (4), the group 0 has x
binding sites, each of which binds one of the x polymerizable
groups P.sup.2.
[0197] In a preferred embodiment Q is represented by
O(Sp.sup.2).sub.2, N(Sp.sup.2) NH(Sp.sup.2).sub.2,
C(Sp.sup.2).sub.4, CH(Sp.sup.2).sub.3, or CH.sub.2(Sp.sup.2).sub.2,
wherein is Sp.sup.2 is a linear alkylene chain having 1 to 20
carbon atoms, preferably 1 to 10 carbon atoms, a branched alkylene
chain having 3 to 20 carbon atoms, preferably 3 to 10 carbon atoms,
or an aromatic or heteroaromatic moiety having 3 to 14 carbon
atoms, preferably an aromatic moiety having 6 to 14 carbon atoms,
wherein each Sp.sup.2 is bound to a polymerizable group
P.sup.2.
[0198] In a further preferred embodiment Q is represented by
"Ar-Sp.sup.3-Ar", wherein Ar is an aromatic or heteroaromatic
moiety having 3 to 14 carbon atoms, preferably an aromatic moiety
having 6 to 14 carbon atoms, and Sp.sup.3 is a linear alkylene
chain having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms,
a branched alkylene chain having 3 to 20 carbon atoms, preferably 3
to 10 carbon atoms, or an aromatic or heteroaromatic moiety having
3 to 14 carbon atoms, preferably an aromatic moiety having 6 to 14
carbon atoms, wherein each Ar is bound to a polymerizable group
P.sup.2.
[0199] In a further preferred embodiment Q is represented by
"Sp.sup.4-Y-Sp.sup.4", wherein Y is a mono- or polycyclic alkane
moiety having 3 to 20 carbon atoms, preferably 3 to 10 carbon
atoms, and Sp.sup.4 is absent or a linear alkylene chain having 1
to 20 carbon atoms, preferably 1 to 10 carbon atoms, a branched
alkylene chain having 3 to 20 carbon atoms, preferably 3 to 10
carbon atoms, or an aromatic or heteroaromatic moiety having 3 to
14 carbon atoms, preferably an aromatic moiety having 6 to 14
carbon atoms, wherein each Sp.sup.4 is bound to a polymerizable
group P.sup.2.
[0200] In a particularly preferred embodiment Q is selected
from
##STR00039##
[0201] Particularly preferred organic compounds are selected from
the group consisting of:
##STR00040##
[0202] Preferred polyhedralsilsesquioxane compounds to be used as
second monomer are represented by the following structure:
##STR00041##
[0203] wherein:
[0204] R is H, C.sub.1-C.sub.6-alkyl, C.sub.2-C.sub.6-alkenyl,
C.sub.6-C.sub.10-aryl, or C.sub.1-C.sub.6-alkoxy; L is
C.sub.1-C.sub.12-alkylene or C.sub.1-C.sub.12-oxyalkylene, more
preferably C.sub.1-C.sub.6-alkylene or C.sub.1-C.sub.6-oxyalkylene,
wherein one or more non-adjacent C atoms may be replaced,
independently of one another, by --SiR.sup.05R.sup.06--, wherein
R.sup.05 and R.sup.06 each, independently of one another, denote H
or alkyl having 1 to 6 C atoms, more preferably H, CH.sub.3 or
CH.sub.2CH.sub.3;
[0205] P.sup.2 denotes a polymerizable group (P) as defined
above;
[0206] y is an integer from 6 to 12; and x is an integer from 2 to
12, wherein y-x.gtoreq.0.
[0207] Preferred C.sub.1-C.sub.6-alkyl substituents are: methyl,
ethyl, propyl, butyl, pentyl and hexyl.
[0208] Preferred C.sub.2-C.sub.6-alkenyl substituents are: ethenyl,
propenyl, butenyl, pentenyl and hexenyl.
[0209] Preferred C.sub.6-C.sub.10-aryl substituents are: phenyl,
tolyl, xylyl and naphthyl.
[0210] Preferred C.sub.1-C.sub.6-alkoxy substituents are: methoxy,
ethoxy, propoxy, butoxy, pentoxy and hexoxy.
[0211] Preferred C.sub.1-C.sub.12-alkylene substituents are:
methylene, ethylene, propylene, butylene, pentylene and
hexylene.
[0212] Preferred C.sub.1-C.sub.12-oxyalkylene substituents are:
methyleneoxy, ethyleneoxy, propyleneoxy, butyleneoxy, pentyleneoxy
and hexyleneoxy.
[0213] Preferred C.sub.1-C.sub.4-alkyl substituents are: methyl,
ethyl, propyl and butyl.
[0214] In a particularly preferred embodiment, the group L in
Structure (1) is selected from the group consisting of
--(CH.sub.2).sub.n--, --O--(CH.sub.2).sub.n--,
--SiH.sub.2--(CH.sub.2).sub.n--, --OSiH.sub.2--(CH.sub.2).sub.n--,
--Si(CH.sub.3).sub.2--(CH.sub.2).sub.n--,
--OSi(CH.sub.3).sub.2--(CH.sub.2).sub.n--,
--Si(CH.sub.2CH.sub.3).sub.2--(CH.sub.2).sub.n--, and
--OSi(CH.sub.2CH.sub.3).sub.2--(CH.sub.2).sub.n--, wherein n is an
integer from 1 to 6, preferably from 2 to 4, more preferably 3.
[0215] Particularly preferred polyhedralsilsesquioxane compounds
are based on the following Structures 2 to 5, wherein x R
substituents are replaced by x (-L-P.sup.2):
##STR00042##
[0216] wherein R, L and P.sup.2 have the same meanings as defined
above; and wherein x is an integer from 2 to 6 in Structure 2; x is
an integer from 2 to 8 in Structure 3; x is an integer from 2 to 10
in Structure 4; and x is an integer from 2 to 12 in Structure
5.
[0217] The polyhedralsilsesquioxane compounds shown above can be
readily prepared from available precursors, and are easily
incorporated into the polymerizable mixture by appropriate mixing
conditions. For example, maleimide substituted
polyhedralsilsesquioxanes and their preparation are described in US
2006/0009578 A1 the disclosure of which is herewith incorporated by
reference.
[0218] Preferred functionalized inorganic nanoparticles to be used
as second monomer are inorganic nanoparticles which comprise
polymerizable groups P.sup.2 on their surface, wherein P.sup.2
denotes a polymerizable group (P) as defined above. Preferred
polymerizable groups (P) for the functionalized inorganic
nanoparticles are selected from maleimide, dimethylmaleimide,
acrylate, methacrylate, allyl ether and vinyl ether groups, which
are either bound directly or via a group L to the surface of the
inorganic nanoparticle.
[0219] Preferred functionalized inorganic nanoparticles are
represented by the following structures:
##STR00043##
wherein represents an inorganic nanoparticle;
[0220] P.sup.2 denotes a polymerizable group (P);
[0221] L is C.sub.1-C.sub.12-alkylene or
C.sub.1-C.sub.12-oxyalkylene, more preferably
C.sub.1-C.sub.6-alkylene or C.sub.1-C.sub.6-oxyalkylene; and
[0222] x is an integer .gtoreq.2.
[0223] Preferred materials for the inorganic nanoparticles are
selected from SiO.sub.2, TiO.sub.2, ZrO.sub.2, Fe.sub.2O.sub.3,
MgTiO.sub.3, CaTiO.sub.3, SrTiO.sub.3 and BaTiO.sub.3. The
inorganic nanoparticles may be solid or hollow.
[0224] Particularly preferred functionalized inorganic
nanoparticles to be used as second monomer in the present invention
are:
##STR00044##
wherein L and x are defined as above.
[0225] The above representations of the functionalized inorganic
nanoparticles serve for illustrative purposes only and should not
be construed as limiting.
[0226] It is preferred that the functionalized inorganic
nanoparticles to be used as second monomer in the present invention
have a degree of functionalization of 0.001 to 5 mmol/g, more
preferably 0.01 to 1 mmol/g and most preferably 0.05 to 0.5 mmol/g.
The degree of functionalization indicates the molar amount of
polymerizable groups P.sup.2 per unit mass of the functionalized
inorganic nanoparticles.
[0227] The degree of functionalization may vary, depending on the
conditions for functionalizing the inorganic nanoparticles. The
person skilled in the art is able to select suitable conditions for
the functionalization of inorganic nanoparticles from literature
known procedures, so that individually adapted functionalized
nanoparticles with different polymerizable groups and different
degrees of functionalization can be prepared. Suitable
functionalized inorganic nanoparticles and precursors thereof are
also available from commercial sources, such as, for example, from
Sigma Aldrich (e.g. 3-aminopropyl functionalized silica, 660442
Aldrich) or nanoComposix, Inc., San Diego, USA.
[0228] The present invention further provides a method for forming
a copolymer comprising repeating units which are derived from the
first monomer and repeating units which are derived from the second
monomer. The copolymer is a dielectric copolymer which may be
linear or crosslinked.
[0229] The method for forming a copolymer comprises the following
steps: [0230] (i) providing a polymerizable mixture according to
the present invention; and [0231] (ii) polymerizing said
polymerizable mixture to obtain a copolymer.
[0232] The polymerizable mixture comprises a first monomer and a
second monomer as defined above. It is preferred that the total
content of the first monomer in the polymerizable mixture is from
50 to 99.9 wt.-%, more preferably from 80 to 99 wt.-% and most
preferably from 90 to 95 wt.-%, based on the total weight of
polymerizable monomers. It is preferred that the total content of
the second monomer in the polymerizable mixture is from 0.1 to 50
wt.-%, more preferably from 1 to 20 wt.-% and most preferably from
5 to 10 wt.-%, based on the total weight of polymerizable
monomers.
[0233] It is preferred that the polymerizable mixture provided in
step (i) is substantially free of solvent. Substantially free of
solvent means that the content of total residual solvent in the
polymerizable starting material is not more than 10 wt.-%,
preferably not more than 5 wt.-%, and more preferably not more than
1 wt.-%, based on the total weight of polymerizable monomers.
Alternatively, it is preferred that the polymerizable mixture
provided in step (i) comprises one or more solvents, preferably in
an amount of more than 10 wt.-%, more preferably in an amount of
more than 25 wt.-%, and most preferably in an amount of more than
50 wt.-%, based on the total weight of polymerizable monomers.
[0234] It is preferred that the polymerizable mixture is
polymerized in step (ii) by a radical or ionic chain polymerization
reaction or a polyaddition reaction. Preferred polyaddition
reactions are cycloadditions, such as 2+2 cycloadditions, 4+2
cycloadditions (Diels-Alder reactions) or 1,3-dipolar
cycloadditions, or nucleophilic additions, such as Michael
reactions.
[0235] The above-mentioned reaction types and associated reaction
conditions (such as e.g. catalysts, solvents, temperature, time,
concentration, etc.) are known to the person skilled in the
art.
[0236] For example, radical or ionic polymerizations may be carried
out in the presence of radical or ionic polymerization initiators,
which can be activated thermally and/or photochemically. The
skilled person is familiar with suitable radical and ionic
polymerization initiators. For example, cycloadditions may occur
photochemically or in the presence of Lewis acids. The skilled
person is familiar with suitable photochemical conditions and
suitable Lewis acids.
[0237] It is preferred that the polymerizable mixture provided in
step (i) further comprises one or more radical initiators.
Preferred radical initiators are thermally activated radical
initiators and/or photochemically activated radical initiators.
[0238] Preferred thermally activated radical initiators are:
tert-amyl peroxybenzoate, 4,4-azobis(4-cyanovaleric acid),
1,1'-azobis(cyclohexanecarbo-nitrile), 2,2'-azobisisobutyronitrile
(AIBN), benzoyl peroxide, 2,2-bis(tert-butylperoxy)butane,
1,1-bis(tert-butylperoxy)cyclohexane,
2,5-bis(tert-butylperoxy)-2,5-dimethylhexane,
2,5-bis(tert-butylperoxy)-2,5-dimethyl-3-hexyne,
bis(1-(tert-butylperoxy)-1-methylethyl)benzene,
1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl
hydroperoxide, tert-butyl peracetate, tert-butyl peroxide,
tert-butyl peroxybenzoate, tert-butylperoxy isopropyl carbonate,
cumene hydroperoxide (CHP), cyclohexanone peroxide, dicumyl
peroxide (DCP), lauroyl peroxide, 2,4-pentanedione peroxide,
peracetic acid, and potassium persulfate.
[0239] Preferred photochemically activated radical initiators are:
acetophenone, p-anisil, benzil, benzoin, benzophenone,
2-benzoylbenzoic acid, 4,4'-bis(diethylamino)benzophenone,
4,4'-bis(dimethylamino)benzophenone, benzoin methyl ether, benzoin
isopropyl ether, benzoin isobutyl ether, benzoin ethyl ether,
4-benzoylbenzoic acid,
2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole,
methyl 2-benzoylbenzoate,
2-(1,3-benzodioxol-5-yl)-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone,
(.+-.)-camphorquinone, 2-chlorothioxanthone,
4,4'-dichlorobenzophenone, 2,2-diethoxyacetophenone,
2,2-Dimethoxy-2-phenylacetophenone, 2,4-diethylthioxanthen-9-one,
diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide,
1,4-dibenzoylbenzene, 2-ethylanthraquinone, 1-hydroxycyclohexyl
phenyl ketone, 2-hydroxy-2-methylpropiophenone,
2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone,
2-isopropylthioxanthone, lithium
phenyl(2,4,6-trimethylbenzoyl)phosphinate,
2-methyl-4'-(methylthio)-2-morpholino-propiophenone,
2-isonitrosopropiophenone,
2-phenyl-2-(p-toluenesulfonyl-oxy)acetophenone, and
phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide. Typically, such
initiators are radical polymerization initiators which may be
photochemically activated.
[0240] Further preferred photochemically activated radical
initiators are:
##STR00045## ##STR00046##
[0241] Preferably, the initiators for radical polymerization are
activated thermally by exposure to heat or photochemically by
exposure to radiation such as UV and/or visible light.
[0242] Exposure to heat involves exposure to an elevated
temperature, preferably in the range from 40 to 200.degree. C.,
more preferably 50 to 180.degree. C.
[0243] Exposure to radiation involves exposure to visible light
and/or UV light. It is preferred that the visible light is
electromagnetic radiation with a wavelength from >380 to 780 nm,
more preferably from >380 to 500 nm. It is preferred that the UV
light is electromagnetic radiation with a wavelength of s 380 nm,
more preferably a wavelength from 100 to 380 nm. More preferably,
the UV light is selected from UV-A light having a wavelength from
315 to 380 nm, UV-B light having a wavelength from 280 to 315 nm,
and UV-C light having a wavelength from 100 to 280 nm.
[0244] As UV light sources Hg-vapor lamps or UV-lasers are
possible, as IR light sources ceramic-emitters or IR-laser diodes
are possible and for light in the visible area laser diodes are
possible.
[0245] Preferred UV light sources are light sources having a) a
single wavelength radiation with a maximum of <255 nm such as
e.g. 254 nm and 185 nm Hg low-pressure discharge lamps, 193 nm ArF
excimer laser and 172 nm Xe2 layer, or b) broad wavelength
distribution radiation with a wavelength component of <255 m
such as e.g. non-doped Hg low-pressure discharge lamps.
[0246] In a preferred embodiment of the present invention the light
source is a xenon flash light. Preferably, the xenon flash light
has a broad emission spectrum with a short wavelength component
going down to about 200 nm.
[0247] It is preferred that the polymerization in step (ii) takes
place in a time range of up to 5 h, more preferably up to 1 h, most
preferably up to 0.5 h.
[0248] It is further preferred that the polymerization of the
polymerizable mixture in step (ii) takes place at elevated
temperature, preferably at a temperature in the range from 25 to
200.degree. C., more preferably at a temperature in the range from
25 to 150.degree. C.
[0249] There is further provided a copolymer which is obtainable or
obtained by the above-mentioned method for forming a copolymer
according to the present invention. The copolymer is preferably a
linear or crosslinked copolymer, more preferably a linear
copolymer.
[0250] There is also provided a copolymer which comprises at least
one repeating unit derived from the first monomer and at least one
repeating unit derived from the second monomer as defined
above.
[0251] More preferably, the repeating unit derived from the first
monomer in said copolymer comprises a structural unit represented
by the following Formula (5):
[-Sp.sup.1-(MG-Sp.sup.1).sub.m-] Formula (5)
[0252] wherein Sp, MG and m have one of the above-mentioned
definitions.
[0253] Preferably, the copolymers according to the present
invention have a molecular weight M.sub.w, as determined by GPC, of
at least 2,000 g/mol, more preferably of at least 4,000 g/mol, even
more preferably of at least 5,000 g/mol. Preferably, the molecular
weight M, of the copolymers is less than 50,000 g/mol. More
preferably, the molecular weight M, of the copolymers is in the
range from 5,000 to 20,000 g/mol.
[0254] Moreover, there is provided an electronic device comprising
a copolymer according to the present invention. For the electronic
device it is preferred that the copolymer forms a dielectric layer,
more preferably a dielectric layer forming part of a redistribution
layer. The dielectric layer serves to electrically separate one or
more electronic components being part of the electronic device from
each other.
[0255] Finally, there is provided a manufacturing method for
preparing a packaged microelectronic structure, in which a
substrate is provided with a dielectric layer, wherein the method
comprises the following steps: [0256] (1) applying a polymerizable
mixture according to the present invention to a surface of a
substrate; and [0257] (2) curing said polymerizable mixture to form
a dielectric layer.
[0258] It is preferred that the polymerizable mixture further
comprises one or more inorganic filler materials. Preferred
inorganic filler materials are selected from nitrides, titanates,
diamond, oxides, sulfides, sulfites, sulfates, silicates and
carbides which may be optionally surface-modified with a capping
agent. More preferably, the filler material is selected from the
list consisting of AlN, Al.sub.2O.sub.3, BN, BaTiO.sub.3,
B.sub.2O.sub.3, Fe.sub.2O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2,
PbS, SiC, diamond and glass particles.
[0259] Preferably, the total content of the inorganic filler
material in the polymerizable mixture is in the range from 0.001 to
90 wt.-%, more preferably 0.01 to 70 wt.-% and most preferably 0.01
to 50 wt.-%, based on the total weight of the polymerizable
mixture.
[0260] It is preferred that the polymerizable mixture applied in
step (1) is substantially free of solvent. Substantially free of
solvent means that the content of total residual solvent in the
polymerizable mixture is not more than 10 wt.-%, preferably not
more than 5 wt.-%, and more preferably not more than 1 wt.-%, based
on the total weight of polymerizable monomers.
[0261] However, depending on which kind of application method is
used for applying the polymerizable mixture in step (1), it is
preferred that the polymerizable mixture comprises one or more
solvents, preferably in an amount of more than 10 wt.-%, more
preferably in an amount of more than 25 wt.-%, and most preferably
in an amount of more than 50 wt.-%, based on the total weight of
polymerizable monomers.
[0262] The method by which the polymerizable mixture is applied in
step (1) is not particularly limited. Preferred application methods
for step (1) are dispensing, dipping, screen printing, stencil
printing, roller coating, spray coating, slot coating, spin
coating, stereolithography, gravure printing, flexo printing or
inkjet printing.
[0263] The polymerizable mixtures of the present invention may be
provided in the form of a formulation suitable for gravure
printing, flexo printing and/or inkjet printing. For the
preparation of such formulations, ink base formulations as known
from the state of the art can be used.
[0264] Alternatively, the polymerizable mixture of the present
invention may be provided in the form of a formulation suitable for
photolithography. The photolithography process allows the creation
of a photopattern by using light to transfer a geometric pattern
from a photomask to a light-curable composition. Typically, such
light-curable composition contains a photochemically activatable
radical polymerization initiator. For the preparation of such
formulations, photoresist base formulations as known from the state
of the art can be used.
[0265] The layer of the polymerizable mixture, which is applied in
step (1), has preferably an average thickness of 1 to 50 .mu.m,
more preferably 2 to 30 .mu.m, and most preferably 3 to 15
.mu.m.
[0266] It is preferred that the curing in step (2) is carried out
by a radical or ionic chain polymerization reaction or a
polyaddition reaction. Preferred polyaddition reactions are
cycloadditions, such as 2+2 cycloadditions, 4+2 cycloadditions
(Diels-Alder reactions) or 1,3-dipolar cycloadditions, or
nucleophilic additions, such as Michael reactions. Preferred curing
conditions correspond to the preferred polymerization conditions as
given above for the method for forming a copolymer.
[0267] It is preferred that the polymerizable mixture applied in
step (1) further comprises one or more radical initiators.
Preferred radical initiators are described above.
[0268] There is also provided a microelectronic device which
comprises the packaged microelectronic structure prepared according
to the above-mentioned manufacturing method.
[0269] The present invention is further illustrated by the examples
following hereinafter which shall in no way be construed as
limiting. The skilled person will acknowledge that various
modifications, additions and alternations may be made to the
invention without departing from the spirit and scope of the
invention as defined in the appended claims.
Examples
A) Synthesis of Host Material Oligomers
Synthesis of Oligomer 4
##STR00047##
[0271] Step 1: Triethylamine (49.7 g, 0.49 mol) was dissolved in
0.7 l of anhydrous toluene, followed by the addition of anhydrous
methane-sulphonic acid (48.6 g, 0.5 mol). The mixture was stirred
at room temperature for 10 minutes before carefully adding diamine
2 (Priamine.TM., Croda, 77.4 g, 0.14 mol) and dianhydride 1 (50 g,
0.07 mol). Next, the reaction mixture was heated to reflux using a
Dean-Stark apparatus for 12 h.
[0272] Step 2: The reaction mixture was cooled to room temperature
and maleic anhydride (8.7 g, 0.09 mol) was added slowly, followed
by the addition of an additional 10 g of anhydrous methanesulphonic
acid. The mixture was reheated to reflux for about 12 h using a
Dean-Stark trap. After cooling to room temperature, an additional
200 ml of toluene were added and stirring was stopped. The upper
(toluene solution) fraction was carefully separated and the salt
fraction was washed twice with toluene (2.times.500 ml). The
toluene solutions were combined and filtered through a glass funnel
which was tightly packed with silica gel. The silica gel was washed
with an additional 100 ml of toluene and the toluene was removed
under reduced pressure to produce 70 g (85%) of a yellow waxy
resin.
Synthesis of Oligomer 5
##STR00048##
[0274] Dimethylmaleic anhydride (ABCR, 20 g, 0.16 mol) was added
slowly to the reaction mixture of compound 3 (synthesis described
in step 1), followed by the addition of an additional 10 g of
anhydrous methanesulphonic acid. The mixture was reheated to reflux
for about 12 h using a Dean-Stark trap. After cooling to room
temperature, an additional 200 ml of toluene were added and
stirring was stopped. The upper (toluene solution) fraction was
carefully separated and the salt fraction was washed twice with
toluene (2.times.500 ml). The toluene solutions were combined and
filtered through a glass funnel which was tightly packed with
silica gel. The silica gel was washed with an additional 100 ml of
toluene and the toluene was removed under reduced pressure to
produce 87 g of a yellow waxy resin.
B) Synthesis of Additives
Synthesis of Tris-(2-maleimidoethyl)-amine (6)
##STR00049##
[0276] Step 1: Furan-maleic anhydride adduct (Alfa Aesar, 28.5 g,
0.17 mol) was dissolved in 750 ml methanol. Tris
(2-aminoethyl)amine (Alfa Aesar, 5 g, 0.03 mol) dissolved in 250 ml
methanol was added dropwise at 0.degree. C. Next, the reaction
mixture was heated at reflux for 4 h. Methanol was removed and the
concentrated solution (approx. 350 ml) was left to crystallize at
4.degree. C. overnight. The obtained yellow crystals were filtered
and washed with ethyl acetate (19.6 g, 38%).
[0277] Step 2: 7.4 g (0.013 mol) of the product obtained in step 1
was dissolved in 300 ml toluene. The solution was heated to reflux.
After 20 h the solvent was removed under reduced pressure and the
residual solid was dissolved in ethyl acetate and purified by flash
chromatography (DCM/ethyl acetate 60/40). Yield: 4 g (84%).
[0278] .sup.1H-NMR (500 MHz, CDCl.sub.3): .delta.=6.68 (s, 6H),
3.52 (t, J=6.6 Hz, 6H), 2.71 (t, J=6.6 Hz, 6H) ppm.
Synthesis of
1,1',1''-(nitrilotris(ethane-2,1-diyl))tris(3,4-dimethyl-1H-pyrrole-2,5-d-
ione) (7)
##STR00050##
[0280] Tris (2-aminoethyl) amine (Alfa Aesar, 10 g, 0.066 mol) was
slowly added dropwise at 0.degree. C. to glacial acetic acid (75
ml). 2,3-Dimethylmaleic anhydride (Merck, 25.9 g, 0.199 mol) was
added and the reaction mixture was heated at reflux. After 20 h,
ethyl acetate (750 ml) and water (375 ml) were added, the phases
were separated and the water solution was washed twice with ethyl
acetate. The combined organic phase was washed with NaOH (1 N,
2.times.250 ml) and brine (250 ml) and dried over Na.sub.2SO.sub.4.
After filtration, the solvent was removed under reduced pressure
and the residual solid was purified by chromatography (SiO.sub.2,
toluene/ethyl acetate (2:1, v/v). Yield: 26 g (83%) as white
solid.
[0281] .sup.1H-NMR (500 MHz, CDCl.sub.3): .delta.=3.49 (t, J=6.7
Hz, 6H), 2.70 (t, J=6.7 Hz, 6H), 1.94 (s, 18H) ppm.
C) Preparation of Blends & Freestanding Films
[0282] General procedure for blend preparation: A solution of
oligomer 4 or 5 in toluene (25 wt.-%) was mixed with different
amounts of additive (if necessary, dissolved in DMAc or
cyclopentanone) and appropriate amounts of a radical starter.
[0283] Preparation of freestanding films: Freestanding polymer
films were prepared by doctor blading onto glass substrate either
cured thermally or photo-induced (more specified conditions see
different examples). The films could be removed from the glass
substrate by rinsing the polymer with water.
[0284] Mechanical & Thermal Properties:
[0285] Tensile strength and elongation at break (E2B) were measured
on a mechanical testing machine (500 N Zwicki). Young's modulus
(modulus) was calculated by dividing the tensile stress by the
extensional strain in the elastic (initial, linear) portion of the
physical stress-strain curve. Film dimension were typically 25 mm
long, 15 mm wide and thicknesses between 25-100 .mu.m). The
measurements were performed according to the following parameter
set: premeasurement: 0.1 N at an extension rate of 10 mm/min; main
extension rate of 50 mm/min. All experiments were conducted at room
temperature (23.+-.2.degree. C.).
[0286] Thermomechanical analysis (TMA) was performed on 402F3 TMA
(Netzsch) in tension mode. The coefficient of thermal expansion
(CTE) was measured in the range from 20-300.degree. C. under
N.sub.2 atmosphere.
Example 1: Oligomer 4 or 5 with
1,1'-(Methylenedi-4,1-phenylene)-bismaleimide (Aldrich, BM11)
[0287] ##STR00051## [0288] (a) Curing conditions: Oligomer 4 or
5+10 wt.-% BM11; 10 min at room temperature+10 min at 100.degree.
C. (hotplate), 10 J/cm.sup.2 (broadband), 30 min at 175.degree. C.
(hotplate).
TABLE-US-00001 [0288] Oligomer 4 + Oligomer 5 + 10 wt.-% BMI1 10
wt.-% BMI1 Modulus [GPa] 0.065 .+-. 0.009 0.177 .+-. 0.008 E2B [%]
118 .+-. 10 148 .+-. 12 CTE [ppm/K] >6000.sup.# .sup. 34 .+-.
21.sup.# .sup.#CTE between 140-170.degree. C.
[0289] Cured films of oligomer 5 with 10 wt.-% of BM11 exhibited a
nearly 3-fold higher Young's modulus, while having higher
elasticity (E2B) compared to blends with oligomer 4. In addition,
the CTE is drastically reduced to a favorable region. [0290] (b)
Curing conditions: Oligomer 4 or 5+10 wt.-% BM11+5 wt.-% Irgacure
OXE-02 (BASF), 10 min at room temperature+10 min at 100.degree. C.
(hotplate), 10 J/cm.sup.2 (broadband), 30 min at 175.degree. C.
(hotplate).
TABLE-US-00002 [0290] Oligomer 4 + Oligomer 5 + 10 wt.-% BMI1 10
wt.-% BMI1 Modulus [GPa] 0.578 .+-. 0.024 0.411 .+-. 0.012 E2B [%]
91 .+-. 9 167 .+-. 14 CTE [ppm/K] .sup. 531 .+-. 459.sup.# -35 .+-.
60.sup.# .sup.#CTE between 140-170.degree. C.
[0291] Cured films of oligomer 5 with 10 wt.-% BM11 using OXE-02
showed higher elasticity in addition to low CTE values. [0292] (c)
Curing conditions: Oligomer 4 or 5+10 wt.-% BM11+5 wt.-% Irgacure
OXE-02 (BASF)+5 wt.-% Dicumyl peroxide (Aldrich), 10 min at room
temperature+10 min at 100.degree. C. (hotplate), 10 J/cm.sup.2
(broadband), 30 min at 175.degree. C. (hotplate).
TABLE-US-00003 [0292] Oligomer 4 + Oligomer 5 + 10 wt.-% BMI1 10
wt.-% BMI1 Modulus [GPa] 0.788 .+-. 0.032 0.854 .+-. 0.026 E2B [%]
20 .+-. 6 45 .+-. 10 CTE [ppm/K] 78 .+-. 5.sup.# 6 .+-. 31.sup.#
.sup.#CTE between 140-170.degree. C.
[0293] Cured films of oligomer 5 with 10 wt.-% BM11 using radical
thermal initiator in combination with photoinitiator (OXE-02)
showed more favorable values in terms of modulus, E2B and CTE.
[0294] (d) Curing conditions: Oligomer 5+10 wt.-% BM11+5 wt.-%
N1919T (Adeka), 10 min at room temperature+10 min at 100.degree. C.
(hotplate), 10 J/cm.sup.2 (broadband), 30 min at 175.degree. C.
(hotplate).
TABLE-US-00004 [0294] Oligomer 5 + 10 wt.-% BMI1 Modulus [GPa]
0.362 .+-. 0.045 E2B [%] 166 .+-. 18 CTE [ppm/K] 115 .+-. 55.sup.#
.sup.#CTE between 140-170.degree. C.
[0295] (e) Curing conditions: Oligomer 5+10 wt.-% BM11+5 wt.-%
N1919T (Adeka)+5 wt.-% Dicumyl peroxide (Aldrich), 10 min at room
temperature+10 min at 100.degree. C. (hotplate), 10 J/cm.sup.2
(broadband), 30 min at 175.degree. C. (hotplate).
TABLE-US-00005 [0295] Oligomer 5 + 10 wt.-% BMI1 Modulus [GPa]
0.429 .+-. 0.038 E2B [%] 140 .+-. 35 CTE [ppm/K] .sup. 61 .+-.
48.sup.# .sup.#CTE between 140-170.degree. C.
Example 2: Oligomer 4 or 5 with Maleimide 6
##STR00052##
[0297] Curing conditions: Oligomer 4 or 5+5 wt.-% Maleimide 6, 10
min room temperature, 10 min 100.degree. C. (hotplate), 10
J/cm.sup.2 (broadband), 30 min 175.degree. C. (hotplate).
TABLE-US-00006 Oligomer 4 + Oligomer 5 + 5 wt.-% 5 wt.-% Maleimide
6 Maleimide 6 Modulus [GPa] 0.030 .+-. 0.004 0.241 .+-. 0.014 E2B
[%] 150 .+-. 1 71 .+-. 11 CTE [ppm/K] >2500* 305 .+-. 55* *CTE
between 25-35.degree. C.
[0298] Cured films of oligomer 5 with 5 wt.-% maleimide 6 exhibited
more favorable values with respect to modulus, E2B and CTE compared
to oligomer 4.
Example 3: Oligomer 4 or 5 with Dimethyl Maleimide 7
##STR00053##
[0300] Curing conditions: Oligomer 4 or 5+5 wt.-% Dimethyl
maleimide 7, 10 min room temperature, 10 min 100.degree. G
(hotplate), 10 J/cm.sup.2 (broadband), 30 min 175 OC
(hotplate).
TABLE-US-00007 Oligomer 4 + 5 Oligomer 5 + 5 wt.-% Dimethyl wt.-%
Dimethyl maleimide 7 maleimide 7 Modulus [GPa] 0.080 .+-. 0.002
0.048 .+-. 0.002 E2B [%] 215 .+-. 5 268 .+-. 4 CTE [ppm/K] >2000
409 .+-. 149* *CTE between 25-35.degree. C.
Example 4: Oligomer 4 or 5 with
1,1'-(Methylenedi-4,1-phenylene)-bismaleimide (Aldrich, BM11) and
Dimethyl maleimide-SiO.sub.2 (50 nm, nanoComposix)
##STR00054##
[0302] Curing conditions: Oligomer 4 or 5+10 wt.-% BM11+5 wt.-%
DMMI-SiO.sub.2 (nanoComposix, Inc., 50 nm), 10 min room
temperature, 10 min 100.degree. C. (hotplate), 10 J/cm.sup.2
(broadband), 30 min 175.degree. C. (hotplate).
TABLE-US-00008 Oligomer 4 + 10 Oligomer 5 + 10 wt.-% BMI1 + 5 wt.-%
BMI1 + 5 wt.-% DMMI- wt.-% DMMI- SiO.sub.2 SiO.sub.2 Modulus [GPa]
0.079 .+-. 8 0.310 .+-. 25 E2B [%] 219 .+-. 15 132 .+-. 12 CTE
[ppm/K] >6000 .sup. 72 .+-. 24.sup.# .sup.#CTE between
140-170.degree. C.
[0303] Cured films of oligomer 5 having the above-described
constitution showed much higher modulus values in addition to
favorable CTE values.
Example 5: Oligomer 4 or 5 with
1,1'-(Methylenedi-4,1-phenylene)-bismaleimide (Aldrich, BM11) and
Dimethyl maleimide-POSS (DMMI-POSS)
##STR00055##
[0305] Curing conditions: Oligomer 4 or 5+10 wt.-% BM11+5 wt.-%
DMMI-POSS, 10 min room temperature, 10 min 100.degree. C.
(hotplate), 10 J/cm.sup.2 (broadband), 30 min 175.degree. C.
(hotplate).
TABLE-US-00009 Oligomer 4 + 10 Oligomer 5 + 10 wt.-% BMI1 + 5 wt.-%
BMI1 + 5 wt.-% DMMI- wt.-% DMMI- SiO.sub.2 POSS Modulus [GPa] 0.019
.+-. 7 0.178 .+-. 8 E2B [%] 274 .+-. 28 103 .+-. 15 CTE [ppm/K]
>6000 .sup. 99 .+-. 10.sup.# .sup.#CTE between 140-170.degree.
C.
* * * * *